Photoperiod for T5 lit frag tank.

PDR · Oct 12, 2018

I am currently running my 4 bulb t5 fixture on my frag tank from 12pm-8pm. At the current mounting height, the par ranges from 100-150 throughout the tank (all soft coral). The growth is not where I would like it, but I think that may have more to do with nutrients (another thread coming on that).

Would there be any benefit to increasing the photoperiod or should I leave it be?

Check out the "Farm" thread in my sig for more information.

Thanks

Retro Reefer · Oct 12, 2018

Can you lower the fixture? Lengthening photoperiod wouldn’t hurt but I would try to get your par up a little.. currently running my t5’s for 6 hours at about 8” off of water, I have led supplements that ramp up from 9-12 and ramp down from 6-9 giving me a 12 hour total photoperiod.. for what it’s worth I had softies growing like crazy in a ULN tank so I’m guessing its probably more about lighting than nutrients.

PDR · Oct 12, 2018

Retro Reefer said:
Can you lower the fixture? Lengthening photoperiod wouldn’t hurt but I would try to get your par up a little.. currently running my t5’s for 6 hours at about 8” off of water, I have led supplements that ramp up from 9-12 and ramp down from 6-9 giving me a 12 hour total photoperiod.. for what it’s worth I had softies growing like crazy in a ULN tank so I’m guessing its probably more about lighting than nutrients.

I would really prefer not to lower it if possible. As much as I'm in and out of this tank, it would make it a pain. From my research, 100-150 par is about where most of these corals should be kept (if not lower). I'm not sure if nutrients are the issue or not, I just know they are undetectable.

I have kept most of these softies in my DT under lower par (longer overall photoperiod) that has some detectable nutrients and they have grown much better. That's not to say they haven't grown, but some seem to have stagnated and some of my zoas aren't looking great.