Photo-period. How Short

[stubbsz]

Are there min and maxes to your photo-period. Due to wishing to reduce my carbon footprint... and my bill, I thought about cutting back my photo-period. I have 250x2 metal halides(phoenix 14K). I think I'm running about 8 hours right now and wondered if I can go shorter without harm to my corals. I haven't got many successful SPS (having loads of issues) have a few lps and softies and Zoas.

-Adrian

 

[Anonymous]

I have no good definitive answer for you-sorry. It's generally accepted that most things stop photosynthesizing after 12 hours so anything longer than that is really unnecessary in most tanks. As far as how short, IME anything less than 10 hours wasn't effective in my tanks.

 

[Anonymous]

I do 10 hours actinic and 8 hours halides with no problems.

 

[stubbsz]

I have no good definitive answer for you-sorry. It's generally accepted that most things stop photosynthesizing after 12 hours so anything longer than that is really unnecessary in most tanks. As far as how short, IME anything less than 10 hours wasn't effective in my tanks.

When you say, wasn't effective, do you mean, no growth or things were dying or something else?
-Adrian

 

[Anonymous]

Didn't get the growth, tenticle extension, etc. The critters just didn't look right if you know what I mean.

 

[Anonymous]

I run my actinics for 12 hours and my MH for around 7 hr each. Been doing it that wat for over a year and get good growth.

 

[stubbsz]

Didn't get the growth, tenticle extension, etc. The critters just didn't look right if you know what I mean.

I know what you mean. I have exactly that right now.... really bad shape in my tank but I don't think it's the photo-period. Unfortunately, I have no clue what it is and I'm super frustrated.
-Adrian

 

[Anonymous]

We have run 8 hour photo period on an sps tank for months and months and still had lovely growth.

This tank had 2X 250w 14K HQI bulbs. No VHO or anything, the 8 hours was it!