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.

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.

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.

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 :biggrin:

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

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.

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.

1. Tank Depth
2. Light type/wattage/height from water
3. Reflectors
4. What coral do you grow?
5. Do you run carbon or anything else to 'clear' the water?

1. 24"
2. DE MH/250W/6"
3. Lumenmax 3
4. LPS & SPS
5. 1 cup carbon changed monthly

1. 24"
2. 14k 250W HQI @ 7"
3. 3x PFO mini on 5' tank
4. SPS
5. Carbon in sock and Ozone

I don't have any supplemental lighting and I don't like looking at a dark tank so the lights are on for 10hrs. I have good colour and great growth.
1. 29" deep tank
2. 250w 10k xm's with hqi ballasts approx 12" off surface
3. lumenmax elite reflectors
4.sps
5. carbon changed ever 6 weeks or so


If cutting back on the lighting period means increased growth maybe I'll keep the lights on for 15hrs instead:razz:

1. Tank Depth
30"

2. Light type/wattage/height from water
20K radium 400W, 15" from water

3. Reflectors
Spiders - def not the best

4. What coral do you grow?
SPS, nem, goniopora

5. Do you run carbon or anything else to 'clear' the water?
Negative