Another question about Lights

[Darth-Tater]

I have been using 2 250 watt coralvue 14k MH bulbs on my 100 here at home for 6 months now. I also have 4 VHO blue actinics(sp). I do not see any growth on the corals except for the xenia. The zoos, brain coral etc don't seem to prosper. Water conditions are good. Should I buy 10K bulbs? I hear everybody saying how this is spliting and this has beautiful new growth. What brand of bulb and K shouold I buy.

Thanks

DT

[Pacman]

Seems to be a bit on the blue side which might be good for bringing out color, but probably isn't so good for growth. IME brain corals are in general moderate growers even with food supplementation, so don't expect it to double overnight. However most zoas seem to grow pretty quickly if given good conditions and a spectrum which allows them to grow well. My tank has only VHO lighting but my zoas and green star polyps seem to double in size every month or so. I have 1 actinic blue and 2 actinic white.

I would think if you lower your spectral output to a 10k or maybe add a few actinic whites on your VHO setup you would probably see more growth.

[JimD]

Theres a lot more to getting good growth than lights. That being said, what are you doing to keep Ca and Alk in check? What about flow? How deep is the tank? Lots of variables involved, lights are just one of them.

[matt]

Yep, Jim's right. Lights are only part of the picture; simply saying "water conditions are good" is a little suspicious to me, no offense intended!

[Richard]

Before you go out and buy new lights you should do some substantial water changes and see if that gets them going. I have gotten excellent growth off of the cv 14k's in the past. When things stopped growing I switched to 10k's and it really didn't make much difference.

All of my water parameters were great but I knew I hadn't done many water changes over the last year. So I just did a 150 gallon water change on my 215 using Reef Crystals salt and OMG the polyp extension on my acros is amazing! Just goes to show, there's more to water quality then you can test for.

[NaCl_H2O]

DT, not to hijack your thread, but this is a very interesting topic! My bug treatment resulted in HUGE water changes! Everything, even softies, fish, and coralyn algae are looking better! So, what are we adding back (or taking out) that we couldn't test for? Trace elments, dissolved solids, what? I am going to keep my water change voule up a little from before to see if it keeps things going better.

[Darth-Tater]

Sounds like more water changes are in order. I am happy with the tank :) I just wondered would 10k light be better. :huh I need to start thinking about new lights I need to buy one at a time sooooooo my wife doesn't notice the money gone. :lol