Too much or too little light?

[BHD]

Hello everyone,

I got a sunpower 6x54 with all ati bulbs, hanged 8 inches above the water on a standard 75 gallons tank. All 6 bulbs are on for 6 hours a day.

I place my zoa on the bottom of the tank. However, the zoa paly are getting smaller and smaller, shrinking over time and disappear all together. I tried to raised it up a bit and lower it, but can't find a spot that the zoas will like.

what is going on? Too much light or too little light on the bottom of the tank?

Thanks,
Bao

 

[rogersb]

Why don't you try 4 bulbs and see how they react over the course of a week or so.

 

[BHD]

My tank is full of sps, I can't really take away two bulbs to try that. hummmm

 

[turok]

I always put new polyps in a dark part of my tank.
If they don't open, I move them closer to the lights.
If they turn white, to much light.
If they are dark and closed, to little light.
but I think it is more than just light.
I have lots of water flow.

 

[A. Grandis]

I have an ATI PM fixture over my 75 as well.
Zoanthids and fishes. No problem with the lights.

I don't think there is anything to do with your lights at all.
Why do you think the lights are the answer for the problem?
How often do you change bulbs? How are the SPS?

Grandis.

 

[A. Grandis]

...
Also, what bulbs are you using?
My lights are on for 10 hours a day.
:bounce2::bounce3::bounce1::bounce2::bounce3::bounce1:

What is the temp?
Water params?
Skimmer?
Water changes?
Target feeding?
Other infos??



Grandis.

 

[BHD]

Most of sps are growing well, some of them stuns and not growing.
Its a bare bottom and so I vacuum out the detritus that in the tank and settle in the sump weekly and change 5 gallons of water.
2 clowns, 2 damsel, 2 lyretail anthias, 1 purple tang.
I feed twice a day.
They are all ATI bulbs at 9 Months old.
Dose cal and alk by brs dosers, cal at 450 and alk at 8.5-9
I don't do target feeding at all.
temp is 78.
I think its the light because before changing to the T5, I had them under a 250W MH, and they were fine, growing like weeds. The only different is that now I have the T5 and my tank is cleaner because its a bb and I change water more frequently and more flow.

 

[abugjo]

Really not sure but I would think that your lights are not on long enough I have a 20 gallon with 4X24 watt T 5s and they are on 11 hours a day. I have zoos, SPS and LPS which are doing great bird nest put on a 1/4 inch in a month. I would think a photo period of only 6 hours is way to short and especially for SPS.

 

[A. Grandis]

What ATI bulbs you've got?

Try to ***very slowly*** bring your timer for more hours a day.

There must be something else going on. I still don't think it could be the lights.

Bacteria, fungus, predators...

Grandis.