T5s and bleaching LPS - anyone noticed this?

[sphelps]

Corals should be introduced slowly to different light spectrum and intensities. I suspect the lighting change in general is the problem, if you had them acclimated to T5s and then put a new halide right on top of them they probably won't look to hot either.

[achilles101]

i have 4@54w t5 on 2x4x16 and Im seeing bleaching on my lps , sps are fine checked tank parameters and they are with in specs. I started out with 2@ 54 and noticed they bleaching and thats when I went to the four thinking it wasnt enough light. when tank was cycling I was running normal t5s and the coralline algae was really pink and thick but since going to the high outputs the coralline growth has dropped off and bleached too. tank parameters are the same.Im thinking about lifting t5s 6 inches off tank.

[sphelps]

LPS corals usually have low light requirements and I find many people seem to think they need tons of light like SPS corals. Whenever I've been diving most LPS corals are in deeper waters or in crevices and some of the best LPS tanks I've seen are lit with simple PCs. My first tank was mostly LPS and was lit with a combination of NO and PC, to this day my LPS have never done as good as they did in that tank.

[Myka]

Originally Posted by sphelps

Corals should be introduced slowly to different light spectrum and intensities. I suspect the lighting change in general is the problem, if you had them acclimated to T5s and then put a new halide right on top of them they probably won't look to hot either.

This isn't the case with my tank. My corals were all used to the 2x39w T5s in a 16" deep tank with T5s about 4" off the water surface, and it was the halides that I slammed onto there. Funny thing is that the halide fixture also included T5s, but now the bulbs were all 8" off the surface. The LPS improved colors quite quickly when the lights were changed. The exact same T5s were used in the new fixture. So the difference was height and halides.

[Navarchus]

Myka, What kind of lps?

[sphelps]

Originally Posted by Myka

This isn't the case with my tank. My corals were all used to the 2x39w T5s in a 16" deep tank with T5s about 4" off the water surface, and it was the halides that I slammed onto there. Funny thing is that the halide fixture also included T5s, but now the bulbs were all 8" off the surface. The LPS improved colors quite quickly when the lights were changed. The exact same T5s were used in the new fixture. So the difference was height and halides.

So you're concerned that your corals are improving from better lighting? I'm sorry but I'm confused what the issue is

Perhaps your previous T5s were older and where not producing efficient par or spectrum effecting the corals health and the new lighting helped?? Or maybe your previous T5 spectrum simply didn't show the coral color giving them the appearance of bleaching??

What T5 bulbs were you previously using?

[Myka]

Navarchus, the corals mainly effected were all three types of brains I have (Symphyllia, Trachyphyllia, and Lobophyllia), Duncans, Hammers, and Frogspawns. The brains moreso than the others. I had to keep all of these near the bottom of the tank or they would bleach, they would start to bleach within a week even though polyp extension was good. Once the halides were on the tank all of these corals were placed within 12" of the halides for over a month, and didn't bleach out at all.

Oh come on now Steve, there is no issue, it's a discussion - just an oddity that I was wondering if anyone else shared similar experiences, or had any ideas as to why this would happen. The T5s were the exact same bulbs (as stated above), removed from one fixture put into the new one. One Fiji Purple and one AquaScience 17,500K. However, I noticed bleaching with all the other T5s I had tried in the last 2 years as well (Giesemann and Hagen). I suppose they had different reflectors and different ballasts running them, so there may have been a bit of a change there, but I would think not much. They went from a Hagen fixture to a Degenbao fixture.

[whatcaneyedo]

I recently moved a bleached and dieing caulastrea from the bottom of my 50 gal which is lit by a single 250W 10K MH to my 20gal which has a 24" Hagen Glo with Life Glo and Power Glo bulbs. Almost immediately the coral stopped receding and regained its former color. Now it looks like it will make a slow recovery.

However on the flip side a friend of mine in town switched his 500gal which used to be lit with four 400W 20K XM to all T5 and had nearly all of his SPS near the surface bleach at first.

[torrid_07]

hey, ive just started getting into corals, i have just purchased a zoo, and a kenyan tree (soft coral). now i have 8. 36w t5s in my 75 gal. is this too much light for my new corals? my lights are sitting about 6" off of the water is that fine or should i be lifting them? i have noticed that the coral almost lies down in the subtrate when the lights go off at night. is this normal? anyways any help with my new corals would be THE WORLD, thanks

[Doug]

Nothing is really to bright. Just proper acclimatization is needed.

All this to bright for certain corals now. Bah. In the mid to late ,90s I grew tons of various soft corals and lps corals under my 250w 65K Iwasaki. Not much brighter than those.

Just manage depth and/or lighting periods when changing bulbs or adding new corals, until they are use to the lights. The eggcrate with some window screen also works well for acclimatizing.

You can keep corals that require less light down on or near the bottom, with proper lighting, instead of trying to get everything up into the light.