How to tell if SPS has too little light??

[imow]

I am acclimating a few new sps to my 2 X 250 MH in a 72 gallon BF. I have them on the sand for now, and some tips show signs of bleaching. Is this a symptom of too little light?? The tank they came from had the same lighting. I dont want to move them higher in the tank if it is going to do more harm. Thanks

Ken

 

[davelin315]

Are you sure they're bleaching, or are they growing?

 

[pez]

Turning brown doesn't necessarily mean the coral is not getting enough light. What is does mean is it is producing more zooxanthellae. Mostly likely do to more light.

I have a coral that was completely white with blue tips. Under my lighting it is now completely brown with blue tips.

-Tom

 

[MedicineMan1]

Usually the white tips are a sign of growth. If they didn't have enough light they'd turn brown because they'd produce more zooxanthellae to compensate for the lower light (brownish-gold is the color of zooxanthellae).

 

[imow]

This is exactly the point which is confusing....The tips are definately bleaching, but I cant tell if its too much or too little light.

 

[Sue Truett]

2x250w MH over a 72g. bf with sps frags on the sand bed is no way too much light and I wouldn't associate this as a cause for bleaching. Like the others I also associate white tips as a good sign of growth, but I'm sure you can tell the difference between growth tips and bleaching. As to what is causing the bleaching, I don't know. Were they healthy to begin with?? In Eric Bornemans first book page 47, he states " bleaching at the tips may be indicative of too much light or unacclimated specimens". Since I really do not think your case is too much lighting, how did you acclimate the frags to your system???

my 120 sps tank: http://suetruett.homestead.com/home.html www.marshreef.org/members

 

[MedicineMan1]

Are you absolutely, 100 percent SURE the tips are bleaching? What kind of sps are we talking? The growth tips on my monitporas ALWAYS looks white; that's the skeleton that the new polyps will grow on!

 

[davelin315]

White tips = growing coral.

White somewhere else in an irregular pattern that has stuff growing on it like algae = bleaching coral.

If you're in doubt, break off a tip of your coral (you'll want to remove bleaching parts if you don't know why it's bleaching anyway) and then glue that piece down to something else and see what happens to it. My guess is it's growing if it's at the tips. If, however, you see the white area growing, instead of just being present at the tops, it's bleaching, so snap it off anyway if you can't figure out why. By the way, if it was due to light, it would probably bleach from the base up, not from the top down. You're also not burning them with your lights if they're at the bottom of the tank.