View Full Version : White spot
Hi again
I know there have been quite a few threads on white spot and many of you may be bored of talking about this but of all the elements facing a new reefkeeper this seems the most daunting. I've already looked through many of the existing threads and there is some excellent, if sometimes highly technical, information in there. But there's one thing that I haven't found much help on and that's diagnosis. So, as a newbie and for the benefit of other newbies who might look up this thread in future, can I ask for some tips on diagnosis?
First of all my quick summary/impressions of what I have found in threads and text books so far (and for fear of triggering the naming debate again let's be specific here - we're talking about c.irritans or possibly amyloodinium - different parasites but am I right in thinking that they have similar outcomes and treatments?).
In terms of practical stages:
Stage 1. Diagnosis - I'll say more about that in a moment
Stage 2. Actions
Here opinions seem to divide into two main camps.
The first group of opinions (let's call it the laid-back approach) seem to be that marine whitespot pathogens exist in every system to a greater or lesser extent (except maybe those that have had no exchanges with any other system for about a year or more). From time to time these will flare up in fish that are stressed by something and therefore have lowered immunity. Normally this will go away in time with good quality feeding and perhaps use of a UV and/or ozone to prevent spread. So leave affected fish where they are so as not to stress them any further. Reef safe treatments don't work and copper is deadly to all inverts.
The second group of opinions (let's call it the panic-stations approach) seem to be that these diseases can and will wipeout the tank. So get the affected fish out of the tank immediately and into a QT tank for treatment with copper preparations. Also bound up with this view seems to be the idea that long quarantine periods should be used for all fish and inverts introduced to stop the pathogens getting into the tank in the first place.
Does this about sum it up? So am I corrrect in thinking that every newbie is just gonna have to decide for themselves which of these approaches they take?
Now back to the diagnosis bit. I're read lots of comments about mis-diagnosis of white spot diseases but not much about how to diagnose the real thing (and let's be realistic now that no-one without a degree or above in marine biology is going to be taking skin scrapings and analysing them under a microscope). Is it the case that without the microscope diagnosis it's just a best-guess? Or are there observations that can help? - e.g.
What precisely do the spots look like - attached particles, pustules erupting from the skin or what? (This is where the books I have looked at are pretty useless with drawn fish-shapes with white dots on them).
Where on the fishes body are they most likely to appear - head, fins, tail?
How quickly can they appear? e.g. if I buy a perfectly healthy looking specimen at lunchtime and by evening it seems to have spots is this how quickly white spot can start or does that suggest it isn't white spot at all?
My recent experience of this is buying two tangs that had been housed together at an aquatics supplier. Four hours later I could see tiny white spots on one of the tang's fins and a few on it's body. I panicked and isolated him in a QT tank within another 2 hours (once I'd made up my mind to do it). No I didn't QT them first because I don't have a big enough QT tank to house two tangs for 6 weeks. And I didn't QT them separately because I wanted to introduce them at the same time to my main tank to minimise aggression (though now I'm gonna have to face that anyway). Was it really whitespot or just dust? I don't know but it certainly wasn't sand. Have I done the right thing ? Again I don't know.
Sorry this is so long but I think some PRACTICAL advice would be great for those of us who have no confirmed experience of these diseases.
Thanks!
JonW
White spot is a difficult issue IMHO it is often confused with freshwater white spot, Ichthyophthirius multifiliis (ich), and there are many other parasitic diseases and environmental factors that cause white spots on fish Costia, Lympocystis, Gyrodactylus, papilloma viruses, pox viruses, chalimus stages of copepodids, Glochidia larvae, micro bubbles, sand grains etc etc so it is an easy disease to confuse with others and a lot of LFS and aquarists assume it white spot without a proper diagnosis.
Back in 2003 I did put up a post here to answer a lot of these questions and if I can find it I will re-post
But to address Jon’s questions
“we're talking about c. irritans or possibly amyloodinium - different parasites but am I right in thinking that they have similar outcomes and treatments”
No not really C. irritans is a ciliate, Amyloodinium is a dinoflagylate. the latter is very difficult to treat, their life cycles are different and the treatment strategies need to to treat these infections is different. As a rule of thumb C. irritans responds to Amyloodinium treatments but not the reverse. Copper is the treatment of choice for both parasites but at higher levels (2ppm) and a longer course of treatment for amyloodinium. As for the outcome Amyloodinium often leads to mass mortality, properly treated C. irritans should not.
"Reef safe treatments don't work and copper is deadly to all inverts."
I wouldn't agree the problem is reefs are such a complex system the biomass is high but varies hugely tank to tank and if you monitored the levels of a reef safe treatment I'd be willing to bet the 1/2 life of the medication differs from tank to tank. Add in the problem that the volume of water in a reef is at best a good guess due to the differences in the amount and porosity of LR then I wouldn't be surprised if, in many, reef tanks that perceived reef safe medications were under-dosed.
Copper is pretty much death to invertebrates (although some isopods can detoxify it quite well)
“The first group of opinions (let's call it the laid-back approach) seem to be that marine white spot pathogens exist in every system”
There is no evidence of C. irritans existing in every system; this has been shown scientifically in many research papers. This is where confusion between the lifecycles of C. irritans and freshwater white spot or Ich (Ichthyophthirius multifiliis) occurs.
“From time to time these will flare up in fish that are stressed by something and therefore have lowered immunity”
Stress in a complex issue but stress alone will not cause whitepot the parasite has to be present. It does not always lower immunity indeed the initial symptoms of stress are an increased immunity especially in acute phase responses (these are the defence systems that prevent pathogens establishing themselves) and it is chronic stress that can have negative effects.
“Diseases can and will wipeout the tank. So get the affected fish out of the tank immediately and into a QT tank for treatment with copper preparations. Also bound up with this view seems to be the idea that long quarantine periods should be used for all fish and inverts introduced to stop the pathogens getting into the tank in the first place.”
This is down to individual choice, if you wish to take the most successful way to treat C. irritans then copper is the best way forward. It may not suit all aquariums but it one of the most effective treatments. However don’t forget that hyposalinity is also effective (use salinities of 0.017 or lower fro a 4-6 week period).
As the parasite does not persist in a tank then one of the best strategies is to keep it out so yes I agree a Qt tank is an excellent idea.
I’ve read lots of comments about mis-diagnosis of white spot diseases but not much about how to diagnose the real thing (and let's be realistic now that no-one without a degree or above in marine biology is going to be taking skin scrapings and analysing them under a microscope).
The reluctance to use a microscope amazes me, it is pretty much the easiest way to confirm the diagnosis of white spot and for £25 it is easy to buy a child's microscope in just about any toy shop which will proved more than adequate magnification to identify the parasite properly and cost a fraction of the value of the livestock. Skin scrapes are very easy to take especially if the fish are very ill or near death. Simply lightly run a fingernail over the skin and put the small amount of tissue that comes away on a microscope slide.
Is it the case that without the microscope diagnosis it's just a best-guess?
That’s the problem; white spots are a symptom of many disease that can include Costia, Lympocystis, Gyrodactylus, papilloma viruses, pox viruses, chalimus stages of copepodids, Glochidia larvae, micro bubbles, sand grains etc etc so it is an easy disease to confuse with others
What precisely do the spots look like?
IMHE C. irritans cysts look like grains of salt, pure white and slightly raised from the skin.
Amyloodinium appears as a smooth grey/gold “sheen” the individual parasite are very small (like finely ground white pepper) and individual parasites are hard to see.
Where on the fishes body are they most likely to appear?
IMHE C. irritans fins first then spreading to the rest of the body, Amyloodinium often starts on the dorsal fin and spread down across the body first reaching the fins last.
How quickly can they appear?
C. irritans In a few hours 4-8, Amyloodinium more quickly 2-4 hours post infection. But the parasite need to be in the aquarium the fish is introduced to or living in. It doesn’t appear De Novo.
Was it really whitespot or just dust? I don't know but it certainly wasn't sand. Have I done the right thing ? Again I don't know.
Hard to say, without a better diagnostic when you caught the fish there was an opportunity to take a skin scrape and be sure. Did you treat it or did it resolve in the QT? if the latter I’d suggest it wasn’t C. irritans or Amyloodinium
My 2003 post
OK Marine white, spot hot topic, little knowledge in the scientific communities or is there? At the end of this post is the 33 peer reviewed references published on this parasite since 1981 so if anyone wants to read all the literature on the subject here is the source material.
But these are the highlights from this work.
White spot is a man made disease
Cryptocaryon irritans is a wild disease (see Ben Diggles papers), with strain variations, and can be found on wild fish, it is rarely fatal in the sea due to the dilution effect and the quirk of parasite distribution i.e. most animals have a low population of parasites (the sea is a big place and a considerable dilution effect of an infectious agent can occur) which do not adversely affect them but a few are highly infected and can become debilitated. This is the underdispersed/overdispersed model for parasite infections.
Why is it so bad in tanks?
There is a finite volume of water thus the parasite burden can increase causing a severe infection in the sea there is a considerable dilution effect so the infection rarely build up to life threatening levels
Stress is the cause isn’t it?
No Cryptocaryon irritans is the cause, stress can be a contributory factor to increasing susceptibility to the parasite but it does not cause the disease. It is possible to have highly stressed fish that have no infectious diseases providing there are no pathogens in their environment.
Every tank has white spot.
Not true. It is a common parasite but once eliminated it can only be reintroduced via new fish/tank water from an infected source. however I'm sure a lot of tanks have low level infection that is kept in check due to the fish having an acquired immunity (which is repeatedly boosted every time a parasite settles on the fish). It only when a susceptible fish is introduced do you get an outbreak (how many times do we see on UR the "my tank has been fine for months but I put in a new fish which has now got white spot, all the rest of the fish seem fine and they have been in the tank for ages" QED
What’s the best cure?
Drugs (sorry but it’s true) copper, quinine, metronidazole, fucidic acid to name but a few
then Ozone
UV possibly but you need very high spec equipment
What else works?
Lower salinity 1.017 for a few months 1.010 for a few weeks. But these are stresses too and can have undesired effects on the fish (fish may become more susceptible to other infections and this treatment can knacker inverts)
What about garlic?
Show me the evidence, proper controlled trials and I’ll believe it until then it’s just £20 a bottle hocus pocus. As for the placebo effect I think one will find it is the psychological belief that you are taking a beneficial medicine that helps the patient recover. As the fish are unaware of the concept of beneficial medicine it’s not going to work.
Immunology.
Can the fish become immune?
Yes they can become immune as the infection progresses and develop natural immunity to the parasite. Is this why the infection may resolve suddenly? Very probably.
Could we use a vaccine?
Yes (see Kurt Buchmann’s papers) but there isn’t a commercial one out there (the vaccine manufactures consider the market far too small.)
Isn’t it true you have to infect an animal for a vaccine to work.
No, not all vaccines require the animal to be infected often just inserting the killed pathogen or a particular protein or virulence factor is enough. Once antibodies (or cell mediated immunity) has been developed in the host then the animals are protected
Improving the nutritional content of the food will boost the immune system of the fish?
Not true adding immunostimulants to the food will boost the immune system of the fish Improving the quality of the food will improve growth, reproduction and fitness
References
Alvarezpellitero P., Sitjabobadilla A., Francosierra A. & Palenzuela O. (1995) Protozoan Parasites of Gilthead Sea Bream, Sparus-Aurata L, from Different Culture Systems in Spain. Journal of Fish Diseases 18:105-115
Bricknell I.R. & Bowden T..J. (2003) Immunostimulants and their role in fish health management Fish Farmer Magazine 26:10-11
Bryant M.S., Lee R.P., Lester R.J.G. & Whittington R.J. (1999) Anti-immunoglobulin antisera used in an ELISA to detect antibodies in barramundi Lates calcarifer to Cryptocaryon irritans. Diseases of Aquatic Organisms 36:21-28
Buchmann K., Lindenstrom T. & Bresciani J. (2001) Defence mechanisms against parasites in fish and the prospect for vaccines. Acta Parasitologica 46:71-81
Burgess P.J. & Matthews R.A. (1994a) Cryptocaryon-Irritans (Ciliophora) - Photoperiod and Transmission in Marine Fish. Journal of the Marine Biological Association of the United Kingdom 74:535-542
Burgess P.J. & Matthews R.A. (1994b) A Standardized Method for the in-Vivo Maintenance of C. Irritans (Ciliophora) Using the Gray Mullet C. Labrosus as an Experimental Host. Journal of Parasitology 80:288-292
Burgess P.J. & Matthews R.A. (1995a) Cryptocaryon Irritans (Ciliophora) - Acquired Protective Immunity in the Thick-Lipped Mullet, C. Labrosus. Fish & Shellfish Immunology 5:459-468
Burgess P.J. & Matthews R.A. (1995b) Fish Host-Range of 7 Isolates of C. Irritans (Ciliophora). Journal of Fish Biology 46:727-729
Colorni A. (1985) Aspects of the Biology of Cryptocaryon-Irritans, and Hyposalinity as a Control Measure in Cultured Gilt-Head Sea Bream Sparus-Aurata. Diseases of Aquatic Organisms 1:19-22
Colorni A. (1987) Biology of Cryptocaryon Irritans and Strategies for Its Control. Aquaculture 67:236-237
Colorni A. & Diamant A. (1993) Ultrastructural Features of Cryptocaryon Irritans, a Ciliate Parasite of Marine Fish. European Journal of Protistology 29:425-434
Diggles B.K. (1997) Some information on the morphology of Cryptocaryon irritans from South-East Queensland, Australia. European Journal of Protistology 33:200-210
Diggles B.K. & Adlard R.D. (1995) Taxonomic Affinities of Cryptocaryon-Irritans and Ichthyophthirius-Multifiliis Inferred from Ribosomal-Rna Sequence Data. Diseases of Aquatic Organisms 22:39-43
Diggles B.K. & Adlard R.D. (1997) Intraspecific variation in Cryptocaryon irritans. Journal of Eukaryotic Microbiology 44:25-32
Diggles B.K. & Lester R.J.G. (1996a) Infections of Cryptocaryon irritans on wild fish from southeast Queensland, Australia. Diseases of Aquatic Organisms 25:159-167
Diggles B.K. & Lester R.J.G. (1996b) Influence of temperature and host species on the development of Cryptocaryon irritans. Journal of Parasitology 82:45-51
Diggles B.K. & Lester R.J.G. (1996c) Variation in the development of two isolates of Cryptocaryon irritans. Journal of Parasitology 82:384-388
Hirazawa N., Oshima S., Hara T., Mitsuboshi T. & Hata K. (2001) Antiparasitic effect of medium-chain fatty acids against the ciliate Cryptocaryon irritans infestation in the red sea bream Pagrus major. Aquaculture 198:219-228
Hirazawa N., Oshima S. & Hata K. (2001) In vitro assessment of the antiparasitic effect of caprylic acid against several fish parasites. Aquaculture 200:251-258
Huff J.A. & Burns C.D. (1981) Hypersaline and Chemical Control of Cryptocaryon-Irritans in Red Snapper, Lutjanus-Campechanus, Monoculture. Aquaculture 22:181-184
Jee B.Y., Kim K.H., Park S.I. & Kim Y.C. (2000) A new strain of Cryptocaryon irritans from the cultured olive flounder Paralichthys olivaceus. Diseases of Aquatic Organisms 43:211-215
Kakuta I. & Kurokura H. (1995) Defensive effect of orally administered bovine lactoferrin against Cryptocaryon irritans infection of red sea bream. Fish Pathology 30:289-290
Lipton A.P. (1993) Cryptocaryon-Irritans (Protozoa, Ciliata) Infection among Aquarium-Held Marine Ornamental Fish and Its Control. Current Science 65:571-572
Matthews B.F., Matthews R.A. & Burgess P.J. (1993) Cryptocaryon-Irritans Brown, 1951 (Ichthyophthiriidae) - the Ultrastructure of the Somatic Cortex Throughout the Life-Cycle. Journal of Fish Diseases 16:339-349
Matthews R.A. & Burgess P.J. (1995) Cryptocaryon Irritans (Ciliophora) - Primary Infection in Thick-Lipped Mullet, Chelon Labrosus (Risso). Journal of Fish Diseases 18:329-335
Novoa B., Nunez S., Fernandezpuentes C., Figueras A.J. & Toranzo A.E. (1992) Epizootic Study in a Turbot Farm - Bacteriology, Virology, Parasitology and Histology. Aquaculture 107:253-258
Ogawa K. & Inouye K. (1997) Parasites of cultured tiger puffer (Takifugu rubripes) and their seasonal occurrences, with descriptions of two new species of Gyrodactylus. Fish Pathology 32:7-14
Pironet F.N. & Jones J.B. (2000) Treatments for ectoparasites and diseases in captive Western Australian dhufish. Aquaculture International 8:349-361
Rigos G., Pavlidis M. & Divanach P. (2001) Host susceptibility to Cryptocaryon sp infection of Mediterranean marine broodfish held under intensive culture conditions: a case report. Bulletin of the European Association of Fish Pathologists 21:33-36
Wright A.D.G. & Colorni A. (2002) Taxonomic re-assignment of Cryptocaryon irritans, a marine fish parasite. European Journal of Protistology 37:375-378
Wright A.D.G. & Lynn D.H. (1995) Phylogeny of the Fish Parasite Ichthyophthirius and Its Relatives Ophryoglena and Tetrahymena (Ciliophora, Hymenostomatia) Inferred from 18s Ribosomal-Rna Sequences. Molecular Biology and Evolution 12:285-290
Yoshinaga T. (2001) Effects of high temperature and dissolved oxygen concentration on the development of Cryptocaryon irritans (Ciliophora) with a comment on the Autumn outbreaks of cryptocaryoniasis. Fish Pathology 36:231-235
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PS I'll offer a free pint if anyone can guess the paper(s) I wrote in that little lot!
What’s the best cure?
Drugs (sorry but it’s true) copper, quinine, metronidazole, fucidic acid to name but a few
then Ozone
UV possibly but you need very high spec equipment
What about garlic?
Show me the evidence, proper controlled trials and I’ll believe it until then it’s just £20 a bottle hocus pocus.
I agree drugs are the best cure but is it worth the stress and upheaval of catching infected fish to put them in quarantine if the outbreak isn't too bad, if the fish is feeding and not showing signs of distress IMO it's best left in the tank.
Garlic, nothing scientific here and by no means a cure however I have seen vast improvements in 24 hrs using Dried Garlic Granules from the supermarket, I put two teaspoons of it in a bag and place it in the sump and change it every two days. It smells quite strong and causes me a lot of ear ache (the bi boobied one can't stand garlic) but it works for me.
John.
Thanks very much Wombat for your comprehensive reply and thanks also to JohnT.
This does answer lots of my questions.
A couple of further responses to Wombat's points -
1. You think that reef-safe treatments might work if they were properly dosed? That's very interesting. I already have some Esha Oodinex and I wonder if this might work in the main tank (if I had an outbreak there)?
2. The microscope thing - it's not the microscope that puts me off (and I assume other people too). Infact I'd be happy to buy one and very interested to see what the pathogens look like close-up. It's the skin scraping that bothers me. Firstly because catching the fish can be a real pain and secondly the thought of trying to hold down a fish that's thrashing about and scraping it's skin with my fingernail fills me with, well horror really. Sorry it's probably just me being squeamish but I don't think I could bring myself to do that. So I guess I'm just left with the guessing. It's a shame that the white spot cysts sound so hard to identify visually.
All this pretty much leads me to the conclusion that if I get through this latest incident white-spot free that it's no more fish for my tank. I'll stop there. I can well do without the stress (get enough of that at work).
JonW
I agree drugs are the best cure but is it worth the stress and upheaval of catching infected fish to put them in quarantine if the outbreak isn't too bad,
If really is marine white spot or amyloodinium (marine velvet) I'd suggest it is bad. If you only have a few spots it is at an early stage and likely to get worst
re garlic
Dr Bee posted this in another post dealing with immunostimualnts and there role in whitespot control (in fish health under the thread entitled whitespot started by nemoclam) and I hope he doesn' t mind if I cite it here
Unfortunately garlic has been lumped in this class of immunostimulants for fish because of its very beneficial effects in mammals (which aren’t really immunostimulatory but microbiocidal). Research in fish has shown that feeding garlic doesn’t have a beneficial effect in fish. Wombat’s post in this tread is quite right (even if the exchange became a bit prickly) when it comes to demonstrating the effect of garlic in Atlantic salmon. So I always advise against it use because there is no evidence that it is beneficial in these cases and it has been shown to induce liver and cardiac lesions in fish fed garlic (probably due to the garlic oil as marine fish do not have the digestive enzymes available to deal with these lipids).
You think that reef-safe treatments might work if they were properly dosed?
I do, I've used quinine and fusidic acid in reefs with white spot and providing the dose is right it worked a treat (although quinine is not tolerated well by bivalves). But I do think accurate dosing is required
It's the skin scraping that bothers me. Firstly because catching the fish can be a real pain and secondly the thought of trying to hold down a fish that's thrashing about and scraping it's skin with my fingernail fills me with, well horror really
Ah I see ;) I'm not suggesting that people chase they're fish around just to take a skin scrape every day, but if the fish is very ill and not moving much (so it is very easy to catch) or freshly dead, then a skin scrape is a real diagnostic help as it can help include or exclude lots of problems, and allow correct treatment to stop a minor problem getting out of hand.
Also if you are catching a fish to put in QT tank then running your finger nail (or other firm object like the edge of a microscope slide) over the skin isn't really going to increase the stress level, they will be sky high because of the netting. If the fish is thrashing around in the net then put the mucus from the net on a slide and look at that, as that too will be loaded with external parasites if that is a problem.
I've done 1,000's of scrapes on sick commercial and tropical fish species, I am happy to say that none have died from the procedure.
Particularly addressed to Wombat but also anyone else who might know this...
One of my fish has now died and the cause is unknown. I don't like not knowing what I am dealing with here and you said the only way to be sure is by viewing skin scrapings under a microscope. Well I have just bought myself a microscope (actually found lots on the high street in Natural World - really quite inexpensive). So my next question is how do I work out what it is that I'm looking at? Do you know of any good websites with microscope pictures of c.irritans and amyloodinium and ideally lots of other pathogens that might cause problems in an aquarium?
Thanks
JonW
This is not bad
http://edis.ifas.ufl.edu/FA041
but no cryptocaryon on there but you can compare with the C. irritans images here
http://www.tfhmagazine.com/default.aspx?pageid=200
Also try to get hold of J.D. Smyth Introduction to Animal Parasitology (http://www.abebooks.co.uk/servlet/BookDetailsPL?bi=536987969&searchurl=bx%3Doff%26sts%3Dt%26ds%3D30%26bi%3D0%26 an%3Dj.%2Bd.%2Bsmyth%26y%3D0%26x%3D0%26sortby%3D2)
there are a couple on abe books (www.abebooks.co.uk (http://www.abebooks.co.uk)) for £2-3 at the moment (a good book but mostly illustrated with line drawings). If you want a really good book on fish health in general (with lots on parasites) then go for
BSAVA Manual of Ornamental Fish (Paperback)
but it's £85 from Amazon
Thanks Wombat!
Blimey 85squid for a book! haven't paid that much for a book since leaving Uni (why is it that poor students have to pay so much for text books? I know supply and demand...)
I'll try out the websites first.
Now I just have to get a skin scraping. I suppose it's being too optimistic to hope that I might be able to identify any of the free-swimming stage pathogens by looking at water droplets?
JonW
I suppose it's being too optimistic to hope that I might be able to identify any of the free-swimming stage pathogens by looking at water droplets?
A little, but it depends how many there are, in bad infections of Amyloodinium I've seen them swimming free in the water.
I got the library to buy "my" BSAVA manual :D
Sorry Wombat
One further question -
re-reading your response above you say:
How quickly can they appear?
C. irritans In a few hours 4-8, Amyloodinium more quickly 2-4 hours post infection. But the parasite need to be in the aquarium the fish is introduced to or living in. It doesn’t appear De Novo.
Does this mean that fish that have been in an LFS tank for 4 days without showing any symptoms and then show symptoms within 4 hours of being in my tank probably haven't carried the disease into my tank? And that it's more likely that the disease was present in my tank before that? This would let my LFS off the hook but I'm not sure it would explain why my previous fish showed no symptoms in 2 months...
Thanks
JonW
The are a few possibilities
1 you were unlucky and bought a fish that was already infected where the tomites has settled on but not completed invaded the skin but not developed into white spots yet (not as rare as you would think as many LFS use copper to keep marine white spot in check, when back home in a reef tank there is no copper (all being well) so the tomites can go about their business unhindered). Especially if the dose of copper was sub lethal for the parasite just enough to slow it down but not kill it.
2 The disease was present at low levels in you tank, but because it was a low continuous exposure your resident fish have developed some/good/limited immunity the new fish being naive to the parasite (i.e. fresh from the sea) doesn't have any immunity so it gets invaded rapidly by the parasite
3 it wasn't white spot but another problem that causes white spots
I'd go with 1 or 2 as the likely scenario here but hard to say which one in reality
Ok thanks Wombat. Since they were in a tank with inverts at the LFS I'm guessing they weren't in water with copper.
So maybe options 2 or 3.
Just been trying out the microscope. I know you said that a £25 toy one would be fine for this stuff but have you actually tried one? I bought a £40 model and so far it seems pretty crap. Tried to view a droplet of the water from the tank and all I can see is a fuzzy blur. The slides are made of plastic and the 'cover glasses' are just circular bits of cellophane! Reckon a scientific grade microscope is out of my price range too.
Still it really does start to mystify me as to where the pathogens in my tank came from....
JonW
I have but you are right a scientific grade on is best
I recommend you get glass slides and cover slips. If you are having trouble focusing or finding things make a mark on the slide with a magic marker to focus on and as a marker to your specimen.
Re the scenarios, but it may have been infected at the wholesalers if the LFS had only had it for 4 days
I've just solved my white spot problem I've swapped my Regal Tang for two cleaner shrimp at the LFS :D I am a bit sad though I've had him nine months and he is fighting fit full bodied and a real beaut but white spot every few weeks I can do without :eek: I hope his next owner has more luck.
John.
Shame great fish if you can keep them away from parasites
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