Do I have too much?

I am having a heck of a time figuring out what is too much vs. too little lighting on my tanks. There are two that are in question:

First is an 80g- 48" x 24" x 16" deep. It houses all soft corals as well as LPS. All corals are on frag crate about 3" off the bottom of the tank. The fixture on that one is a T5HO 8 bulb, individual reflectors and I am running 4 x 10k and 4 x actinic (coralife). I have the fixture about 8" off the surface. All of the corals in that tank seem to be doing okay but compared to every LFS I've been to, it seems that their lighting is far, far lower than this. There are a few things that I think could look beter and don't know if the light is too bright. They have been under this light for over a month. Incidentally, I was looking for a bulb that would hep bring out some of the reds a bit more so any suggestion on those would be welcome.

Next tank is my 47 bow. I started off with just a 3 bulb T8 fixture for a couple weeks running 2 x 10k and 1 actinic. I have since upgraded and am using a 2-bulb T5HO fixture (shared reflector) and have two actinics in that. I was still using the T8 fixture as well with just 2 bulbs in it and had the actinic and 10k and things were doing okay. A couple weeks later I removed the T8 fixture and added a second 2xT5HO with 2x10k. It was my plan to end up with these two fixtures. After doing that the corals were not happy. The SPS on top were fine (no surprise) but one of my hammers and my blasto would not open for 2 days (both are on the bottom of the tank). I swapped out the second T5HO fixture for the T8 and they opened up the next morning. My question here is if the 4 T5HO bulbs will be too much for this tank. I would not think so but again, much brighter than most of the LFS around here. When is there too much light in a tank?

 

I think the reason your Lps closed for a couple of days was because of the sudden light change. A four bulb t5 is far from too much. Too much would be a 400w MH over a 10 gallon. It's hard to go over with t5.

 

Oh and if you want to bring out the reds, I'm PRETTY sure that they make red and purple bulbs.

 

Do you feed your Lps?

 

Yes, I do and they are doing very well. I plan to acclimate the 47 BF to the brighter light gradually but wanted to be sure it was not going to be too much. I guess the LFS around here just have their tanks underlit.

 

Yeah and alot of lfs will accent with magenta LEDs to make there corals look better.

 

Blasto's and Hammers generally like less light. It is just as easy to overdue lighting with t5's as it is with any other fixture. How many watts are your t5's? It is also important to acclimate your corals slowly to any change in lighting. You can do this by either adding bulbs one at a time or by shortening the light cycle and gradually lengthening it.

 

The 48" T5s are 54w and the 36" ones on the 47bf are 36w. The problem with the 2-bulb fixtures on the 36" tank is that they only work with 2 bulbs in them. The only way I can figure to do it gradually is to place screen under one of the fixtures to shade the tank, and then take pieces off over time to increase the intensity.

 

You will most likely need to move your fixtures to 24" to 30" above the sand on the BF and to 30" on the 80.