Too much light?

[bryman]

Did some searches but still didn't find the answer.

I seem to have a few weird things going on with some of my SPS. My tank parameters are all where they should be. Decent skimmer, dosing system, dosing MB7 and vodka conservatively. Some corals are thriving, some are not.

In particular, I have seen some of my SPS display encrusting rather than growing up behavior. I have seen this with several stags, millepora, and other acros. One of the staghorns is even branching back down towards the rock instead of towards the light. Then again, my birdsnest, red planet, and monti cap are doing great. Also, a few of my acros have turned rather brown, although they are growing and appear healthy.

I have only 2 fish in the 90G - a rabbitfish and a ocellaris clown. I don't overfeed and switch off between different Rod's frozen and Spectrum pellets once a day, skipping about a day a week.

My acan lords and other LPS near the bottom are a little shriveled, and could look better.

Which all leads me to believe that maybe I have too much light??? Right now I have a 6 bulb ATI Sunpower a "fist" above the tank (about 5" above the water). What do you guys/gals think? Your help is appreciated

And sorry no pics - light is off

 

[Felixc395]

Would you mind posting your parameters? I know you said they're fine but that's sort of vague. Especially post nitrate, phosphate, calcium, alkalinity, salinity, magnesium, and really anything you test for.

Also what test kits are you using? Some test kits can be unreliable or jus expired.

How tall is your tank? What size tank? The sunpower is a very high output fixture but if your sps had too much light they would bleach rather than brown out which is a nutrient problem.

And when you say some sps are encrusting that's perfectly normal. They're just expanding their base. And if you have an ORA red planet doing well than things must be good because they're pretty sensitive.

 

[bryman]

BTW, for flow, I have two MP40s. I run them on reef crest or wave mode usually. Tank temp is 78.

 

[Felixc395]

Well than flow certainly isn't your issue, neither is temperature unless you have large, daily swings.

 

[Radioheadx14]

Maybe they are not getting enough food with only 2 fish in there.

 

[bryman]

You know what - I started feeding Reef Chili about a month ago and SPS growth has at least tripled and colors are improving. I feed Rods food to the fish about 3-4x a week, but I don't think it was small enough to feed the SPS. Also, my Acans were getting too much light on the sandbed. I moved them to a shaded area on a lower rock and they look much better. That Sunpower cranks out some light apparently.

 

[madkeenreefer]

just a side note if you have hi flow it is quite normal to have SPS encrust befor to branch , they are just growing to their surroundings. they dont want to get blown away now do they .

 

[Logzor]

What is your current lighting schedule and bulb combo? Are your corals suffering from light/pastel colors?

I had a similar setup, with a 7 bulb T5 fixture over a 90g SPS reef. I found that I had much better color and growth when I only used 5 bulbs. At least one of those were actinic. My light schedule was at max 8 hours total.

Try reducing your main light cycle down to only 3 hours, keep everything else the same. See if it helps. It certainly wont hurt anything.