How long is your photoperiod?

[GreenSpottedPuffer]

Interesting...so far most people are either at 12 hours or half that at 6 hours.

I would have never even tried 6 hours until I read the RC thread with people raving about how well their corals responded and the thoughts on photo-inhibition. At least for sps, they can get 'tired' if you give them too much light and not enough 'repair' time from what I understand. Someone likened it to the gym...Your muscles grow 'overnight' as they repair themselves as do sps and like a work out, you can really overdo it. Especially since our lights are stuck at high noon for all these hours. It would be great to have dimable halides and be able to keep my lights on 12 hours a day, fading up to full and then back down over a long period of time. Just don't have the money for that right now.

[Snaz]

Originally Posted by GreenSpottedPuffer

It would be great to have dimable halides and be able to keep my lights on 12 hours a day, fading up to full and then back down over a long period of time.

For nano tanks LED makes this possible.

[PoonTang]

1 24"
2 10k 2x250 HQI 4" from water
3 Aqualight Pro
4 Sps dominated with some LPS, softies, zoo's
5 Carbon in TLF reactor, 1 cup/month. WC 12G / week

Recently lowered photo period from 8 hours to 6 after reading that everyone was getting better results. Havnt noticed any change after 2 months. Going to change bulbs out to 14k Phoenix and give that a try.

[Myka]

I think it's important to know what bulbs/ballast/Kelvin you are using as well to have any sort of idea on PAR.

I voted 4 hours or less. MHs run 4 hours on my tank. Mostly because the lights are too strong for my LPS in the shallow depth of this tank, so I can't run them for the 6 hours I would like to. When I transfer this fixture and all my livestock to my 90 I will run it for the full 6 hours, and I will be upgrading the reflectors and bulbs.

I run actinics for 10 hours a day. One KZ Fiji Purple, and one AquaScience 17,500K.


1. Tank Depth?
14-15" from water surface to sand surface.

2. Light type/wattage/height from water?
2x250w DE Coralife 10,000K on electronic ballasts (bulbs came with fixture, will be changing out), 8 1/2" from water surface.

3. Reflectors?
Crappy ones. Same shape as the typical DE in fixture reflectors, but just smooth mirror finish. Will be replacing them.

4. What coral do you grow?
LPS.

5. Do you run carbon or anything else to 'clear' the water?
Carbon - 1 week on, 1 week off.

[GreenSpottedPuffer]

Originally Posted by Myka

I think it's important to know what bulbs/ballast/Kelvin you are using as well to have any sort of idea on PAR.

This is true and I am even thinking of raising my lights to 22" off the water from 18" and trying a long photoperiod to see how that works. The light should be less intense but longer. The reason is that I can't keep LPS or even some sps in the middle of my tank, even on the bottom. They don't do well except in the shade. Birdsnest literally have to be out of direct light or they start to fade fast. I have also noticed one of my torts in not too happy about half way up directly under one of the lights but if I move it down to the bottom, its fine. Problem is, I don't want it down on the bottom.

[brizzo]

1. 14" Depth
2. 150w HQI, 5" from water
3. Coralife clamp on, stock reflector
4. SPS and LPS
5. No media filter, or skimmer

My photo period is 10 hours a day, and I have some SPS frags about 3" from the water line that are colorful, growing, and encrusting. Pieces I have on the bottom are also doing well, along with Maxima clam that seems to constantly have new skeleton under its mantle

Though I find interest in this 6 hours per day theory, it makes sense with the muscle/workout analogy.

[michika]

I'm amused and interested to read that everyone has lowered their photo periods for the purposes of growth. I did it just to save some cost on energy bills...and it worked. I saw a $40 drop in my bill, which I can't 100% attribute to my lowered MH use, but I do know they contributed.

I also read the thread on RC that a lot of you are referencing. I noticed towards the end, or whenever I stopped reading it, that a lot of people were returning to their old photo periods, or commenting that the growth bursts seem to be short lived. I understood it that people saw some great growth and colouration, and then again it would slow down, but in most cases was still faster growth then when they were running 10 or 12+ hours of lighting.

[BC564]

I went to a smaller period to save money....be it energy cost or bulb life.....it all adds up...and if I get the same results.....its all good.

[BC564]

I run for 6 hours and the corals seem happy.


1. 24"
2. 7- T5 HO's 54 watts each.
3. The fixture is the 48inch Aquactinics Constellation
4. A bit of everything
5. Just started Carbon

[steve fedyk]

I lights are on 8 hours

1 24"
2 2-250w hqi 10" off water
3 giessmen
4 sps
5 zeo and carbon