Photo Period Length

[smithcreek]

I have virtually no nuisance algea in my tank (knock on wood), just a little green film on the side glass that I don't bother to clean off. My photo period was 10 hours, boosted it to 11 a couple weeks ago and just today boosted it to 12. Are there any downsides to a long photo period other than algea? Seems like the corals would appreciate more light.

 

[this is me]

What kind of lighting you have. 12 hours seems kind of long.
I ran my MH light for 8 hours only.

 

[smithcreek]

It's a MH 150 14k. I know most people don't run them that long, but the only downsides I could think of were algae and heat. If those aren't an issue, why not run them longer?

 

[this is me]

Algae is mainly due to nutrient in the tank. Lighting in the wrong spectrum can only promote that.
If you can afford the bill of running your longer, I don't see why not.

 

[NeO]

6 hs here for MH

 

[stevenp]

6 here as well.

 

[smithcreek]

So, no one can think of any other downsides besides algea and heat?

 

[LockeOak]

Shorter bulb life and increased electricity use.

 

[penguinsix]

I run mine for 9 hours.

 

[Dave McReeferson]

I don't think the longer "on" time will effect bulb life as much as expected. I was talking with someone about this at the last meeting, he had run greatly reduced lighting cycles on a few bulbs and found his bulb life was not greatly extended. I think it may be that surge required to fire a bulb and possibly the heating/cooling cycles that most appreciably effect bulb life rather than the total hours of operation. I am not saying total hours does not play a role, just that it may not play as large a role as you may think. I may be off here too, just kind of thinking aloud...

 

[smithcreek]

I don't care nearly as much about replacing a bulb as I do about giving my tank what's best for it. If one or two of my livestock die because I didn't give them enough light I'd be out more money and frustrated. If a long lighting cycle isn't going to hurt anything that's what I'll do. It's only a 150w 14k MH so I'm hoping that extending the lighting cycle is making up for a lower PAR. Not sure if it works that way, but...

 

[RichConley]

Why do you think giving your corals more light is whats best for them?


Corals DO photosaturate. If you give them any more light than the photosaturation point, it just stresses them out, and leads to increased risk.

 

[smithcreek]

Why do you think giving your corals more light is whats best for them?


Corals DO photosaturate. If you give them any more light than the photosaturation point, it just stresses them out, and leads to increased risk.

Why do I think that? I don't, that's why I started this thread. To see if there were some downsides. I guess without using the term photosaturation that's what I was asking, can too much light be a problem. Any where I can find some reading on photosaturation?

 

[chief]

I have (5) 54w T5's and wondering the same thing.. I've been leaving my 2 daylights on for 8 hours and the actinics on for 10-12 swimply because i like to see it on. am I correct into thinking actinics don't really do much for coral growth and that's not effecting the photosaturation process, or is it?

 

[smithcreek]

I'm sure it's an incredibly complex subject with many variables and no simple answer. In "The Reef Aquarium, Vol III" they state 10-12 hours but no more, so I guess I'll just see how my livestock reacts since I'm sure there's no formula.

 

[Glass Ocean]

I'm sure it's an incredibly complex subject with many variables and no simple answer. In "The Reef Aquarium, Vol III" they state 10-12 hours but no more, so I guess I'll just see how my livestock reacts since I'm sure there's no formula.

Maybe there is. I'm not sure it would make any difference in our little systems but we could try and replicate the light in the area of the world our corals come from. For example, Key West ranges from 10.39 Hours of Daylight to 13.38 Hours of Daylight. Assume a couple of hours of diminishing and increasing light using Actinc only and there you have it.