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Sanj
23-12-08, 12:23
Hello all,

I have come from a background in keeping planted freshwater systems. While lighting is a key parameter in the success of such aquariums, it does have its limits and simply throwing more watts at it alone will not improve plant growth. The other key factors obviously include CO2 concentration in the water and nutrients. The reef system is a different environment and I am not sure as to how the science changes.

Sump area dedicated to macro-algae growth is obviously another factor in deciding the lamp wattage to use. I am looking at a mud substrate system where the mud area will be 20”x 14” and water probably 8” deep (total sump probably will be 27”x20”x 18”h). This amounts to 35 litres and I am thinking of using a single interpet 55W compact flourecent which I already having lying around. However that would be 1.6 w/litre or 7 watts per gallon!! In freshwater planted aquaria the range is 0.5-1 w/litre (2-4w/gallon). 4 wpg is the upper end for growing the really high light demanding plants in freshwater. So in this situation I probably have overkill with the lighting. Not least in a reef system it is more likely to my mind that CO2 is the limiting factor, with the amount of turbulence and naturally lower co2 concentrations with higher kH and Ph. Albeit compared to freshwater plants marine macro algae must be well adapted to lower co2 conditions in the sea.

In the ecosystem aquarium I understand that the idea is to have optimum growth of macroalgae in the sump in order for the system to work properly as a nutrient exporter (Nitrates and phosphate in particular). I will probably use my 55w compact fluorescent Daylight tube ~6,500k (ideal for photosynthesis) because I happen to already have it, but I am sure some people are going hugely above this with their lighting when they could be saving the pennies.

Unless I have got something very wrong my thinking is that if you are looking to buy a light for your macro-algae sump, around 4WPG over the growing area would be optimum.

Any thoughts?

Viv
23-12-08, 13:01
Also depends on the duration of lighting.

Some reefers prefer the reverse cycle ie light up when the the main tank is off or in my case, my fuge is 24/7. I have been using a 9w Azoo which is just white light, prior to that the Wave LED which is 0.0064w. Both have their advantages and disadvantages.

Currently experimenting with Wave Solairs, dual blue/white light at 18w.

The macro algae is not just dependent upon nitrates and phosphates, but also other governing nutrients such as iron. I think the more successful of 'fuges are reefers here who hasve a base of miracle mud or the equivalent.

HTH and good luck with your new venture!

Sanj
23-12-08, 14:07
Hello,

yes I will be using MM, I thought about the cheaper alternatives and read numerous posts on various forums, so i could be a muppet, but im going to use it. lol

Will also use 24/7 lighting and not reverse method. :D

Reefdude
23-12-08, 15:26
I've got a 11w arc pod in mine and the racemosa grows like wild fire, running 24/7 :).

Sanj
23-12-08, 15:36
hey reef dude, can you tell me how big the comaprtment is where you grow your algae? Thanks

chew1904
23-12-08, 16:11
I run an 11w arc pod too. Its lit 24/7 and the surface area is only about 2square feet as I'm pushed for space in my sump. The cheato grows well under it though.

kneival
23-12-08, 17:33
I use an interpet plant growth 55w lamp over my 2ft sump, the chaeto grows well.
Not sure I would buy another interpet starter unit as the lamp connector is made very brittle by the heat and eventually makes the bulb impossible to remove...Im on my second one now!!

Reefdude
24-12-08, 14:34
hey reef dude, can you tell me how big the comaprtment is where you grow your algae? Thanks

Hi Sanj, my dsb compartment is pretty small 6" L x 12"W x 8" H, space is a premium in my sump, but it's absolutely full of Caluerpa :).

ourmanflint
09-01-09, 00:17
Using a 45w daylight 6500k bayonet type bulb from fleabay, super bright, tons of PAR and Chaeto growing like crazy, on for 16 hours a day at present on a reverse (mostly) lighting phase.

:D

Haile S
09-01-09, 15:37
two 20 watt energy saving SAD bulbs from the bay. 18 hour reverse(ish) lighting and the chaeto grows like mad. 0 nitrates 0.008 phoshates - very happy :)

Long dave
09-01-09, 15:55
i use 36W PC over mine at the moment and is more than sufficient,
i think im right in saying you can use any PC lower than the Max wattage allowable for the unit,
you could save your self buying a new unit and just get an 18W PC and put it in your PC starter?