is 20k light bad

[79Yota]

I know that 10k light is the best, but if I put a maxima under a 150watt 20k double ended light in only a 30 gallon tank it will be okay, right?

 

[H^2 Salt]

despite what some may say.....a 20k is fine for clams........and in my opening make them look much more colorful.....10k will make them grow faster though......

 

[H^2 Salt]

woops...im my OPINION........

 

[gcrowptc]

tagging along here as I have 10k 175w on 20h with a crocea in the top of the rocks and was thinkingh of going to 14k

 

[PSEUDOREEFER]

My all green crocea gained a slight brown coloration after being taken from a tank with a 10k 175 watt halide to a tank with a 400 watt 20k halide. Both tanks were the same depth and the 400 watt light is much brighter, but the clam changed color anyway because of the changed spectrum.

 

[Peabody]

No...countless reefers have successfully kept clams under them. Is it the best? No...6500k is probably the "best", but there's nothing wrong with higher K bulbs, as long as the PAR is there.

 

[mbbuna]

here is an artical by D. Knop that explains why 20k shouldnt be used for clams.first click on "on the half shell" then if u go down and click on Reef tank design for giant clam lovers u will get to the lighting partwww.aquariumfrontiers.net

 

[mbbuna]

working now

 

[Snprhed]

Yota, I have a similar setup. A 20 long with a 150w DE. Running a Ushio 20K and feeding DT's and my crocea looks great. The clams look great and seem very happy.

 

[manderx]

that's probably an old article. i don't exactly agree with his reasoning, he's mistaking color temp for intensity. clams don't live deep because it's blue, but rather dim. as long as your 20K bulb is bright enough, you'll be fine.

 

[mbbuna]

the higher the k rating the lower the intensity. a 250w 10k bulb has more intensity then a 400w 20k bulbwww.reeffrontiers.com/forums/showthread.php?t=2654&page=1
this thread talks about lighting and how the zoo in corals and clams use light. its a long thread but in the end u will see

 

[PSEUDOREEFER]

My clam is still doing fine and growing well (it's 18" under a 400 watt SE), but the point I was trying to make was that while the clam may live well, it might lose some bright colored pigments as these pigments are meant to protect the clam from being burned from certain spectra. I also have a maxima and derasa under that bulb and neither have lost any color.

 

[mbbuna]

i under stand that. my point is that with bulbs with high k ratings the clams are missing a vital part of the lighting spectrum. im not saying that they wont live but that they would be much healther and happer under a lighting that represents where they would live in the wild,which is shallow water. one misconception with 65k and 10k bulbs is they dont have a lot of blue in them, they do, but the 20k bulbs have almost no greens,yellows and reds that are very imporant to shallow water creatures

 

[PSEUDOREEFER]

Yes, my 20k Coralvues (recently replaced by XM's) have almost no green in them which is why I think I lost much of the green pigment of my crocea. My blue maxima on the other hand has lost no coloration. The derasa hasn't really changed at all, but I think this is more in part because it's over 10", a low light clam and almost directly under the 400.

 

[bigfishman]

I am using 150 DE 20k and all my clams are happy with great color

 

[poon415]

Well if 20k is less than ideal, what about 14k? Are 14k's good enough(14k Phoenix 150w)?

 

[Reefvet]

Well if 20k is less than ideal, what about 14k? Are 14k's good enough(14k Phoenix 150w)?

As posted just above, and in my experience as well, 20Ks do nicely. You will undoubtedly enjoy more growth with 14K and a very nice look as well.

 

[Scuba Dog]

I use the 250 DE 14kAC/phoenix....Clams are great with it excelent color, great price for the hoenix that is, and the PAR numbers are basicly the same as a 10K 250DE Ushio...plus my clams are only in a tank thats 13 inches deep...with a two to three inch sandbed:bum:

The best part is no need for actinics what so ever