10 k or 14 k lamps

[GOTAREEFTOKEEP]

Hi,

All water prams spot on, although still very very slight color change on sailfert no3 tset so im going with 1ppm reading, but i now have an algae bed now well underway to getting this to 0ppm.

Still getting to the problem i have a green algae starting to show on the tanks glass, it's like a green coralline aglae meaning that it's comming in tiny little spots that eventually grow in to agreen mass and it's starting to get to me so with every thing else spot on and growing very well i'm turning my attention to the lighting, 400w twin arcadia 3 with actinics bought second hand with 13 month old bulbs that i've since used for 4 months.

My tank is sps/lps only now would 10k or 14k be better spectrum and also my lighting times are actinics are on at 7.30am through 11.00pm with the hailides comming on at 2.00pm through 10.00pm ok or need to change ???

Matt

[dan-the-man]

I get this too, thought everyone did though, not exactly annoying though lol.

Personally I feel its personal choice but I prefer 14k's and thats what I've got over my tank. If you do go from 10ks to 14ks there shouldnt be too much jump in par as 10ks are brighter but they are older so that should be fine for your corals. :)

The theory is that more par = lower kelvin rating, so, 10ks would mean less growth but a nicer colour

HTH
Dan

[designsonline.co.uk]

Hi could someone confirm or challenge this as I have just been told the exact opposite!

Cheers Joe

[simon garratt]

The 'general' trend is that the Lower the kelvin rating the higher the Par, yes, but there are a few exptions if you match one manufactures lamp against another (mainly becouse the K rating system is pants to be honest) but yes it could be considerd a general trend.

However i will contest the 'growth' theory, (no offence Dan) There are simply far too many alternative factors that negate this as a reasonable claim to base a purchase on outside labratory conditions, from species preferance, to feeding, flow, chemistry, etc etc. its vertually impossible to state catagorically that a difference of a few 1000k will make any difference whatsoever to growth in all cases. As an example its not unusual for staghorn corals to grow thinner and faster under dimmer lighting in an effort to get nearer the light source faster to take advantage of a larger surface area in an effort to fully utilise what light 'is' available.


regards

Si.

[kim]

The 'general' trend is that the Lower the kelvin rating the higher the Par, yes, but there are a few exptions if you match one manufactures bulb against another (mainly becouse the K rating system is pants to be honest) but yes it could be considerd a general trend.

Absolutely.

One thing to remember is that, in a perfect world, generation of one unit of "blue " light needs about 20 % more energy than yellow light, and about 40 % more energy than red light. Yet in PAR terms, it's all the same. So, to get that "blue" you have to pump in more energy (higher wattage lamp) or (with the same wattage) accept fewer units. The world isn't perfect, so the cost is rather more. Hence, the rule of thumb that the more "blue" the less PAR.

PAR, however isn't the only game in town (otherwise the perfect lamp would be red - the most PAR for the fewest bucks).

And the "colour temperature" of a lamp is, as SiG says, really not that helpful. A 10,000 K lamp may emit more blue light than a 14,000 K lamp. The latter may not look blue because it emits a lot of blue light, but simply because it emits pitiably low levels of all light. Its performance in the blue area is marginally less embarassing, so that's the dominant colour. Meanwhile, the 10,000 K lamp may emit sheds of blue, but even more yellow....so it looks yellow !

The eye will tend to play tricks as well.....yellow light will dominate blue and red....

Murky waters. Marketing department's dream !

kim

[simon garratt]

Murky waters. Marketing department's dream

ohhh yes. Lying little hobbitsies.

:D