Actinic Lighting and Hair Algae

[TheReefGeek]

His question was actually:

Can too much actinic lighting be attributed to hair algae growth.

And my answer is no, not any more than lighting in general.
Nutrients are the problem, not the actinics. If you want to solve hair algae with lighting reduction, you will have to kill all your corals to do it.

[Samw]

Curious, does photosynthesis equate to growth in algae? If so, would you expect oxygen to be produced by algae when the lights are on? Because in my tank which contains all sorts of algaes, turning on only Actinics light in a dark unsaturated low oxygen tank produced 0% additional oxygen (when measured by my dissolved oxygen meter). To me, that means photosynthesis is not occuring anywhere in my tank when only the Actinics are on and thus the Actinics can't cause algae to grow significantly (at least not with 96W of it).

[GMGQ]

Well you're getting into semantics now. Obviously you dont want to reduce your lighting to say 1hr/day. But light does "attribute" to HA, in a system that has nutrients.

I stick by my equation of: Nutrients + Light = Algae.

Reduce either Nutrients or Light and the Algae will not grow as profusely.

But I totally agree that the ultimate goal is Nutrients = 0. No question. (BTW, feel free to include Phosphates as part of the problem as well).
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It just sounds like Jaws is a busy guy, sometimes leaving his actinics on from 9am-12am over his nutrient filled tank. In the short term, he definitely doesnt need to leave the actinics on for 15hrs/day. So by getting a timer to automate and reduce the lighting period, he should see some immediate results. The reduction of nitrates is usually a long term process.

Originally Posted by TheReefGeek

His question was actually:

And my answer is no, not any more than lighting in general.
Nutrients are the problem, not the actinics. If you want to solve hair algae with lighting reduction, you will have to kill all your corals to do it.

[Jaws]

The problem is that I'm struggling to find the source of the hair algae growth. I feed twice a day but not very much. The MH's are on for about 10 hours and the actinics for about 14. I switched to RODI water about a month and a half ago but didn't notice a change. I know other people in my area that don't bother with RO water at all and they don't have algae problems to my extent. I use a Euroreef CS8-3+ that pulls a ton of thick black gunk out. I'm not sure how much it should be pulling out on a regular basis though since I have nothing to compare it to. I'm running a Phosban reactor with Rowaphos, a 200mg ozonizer and not to mention manually picking the algae off the rocks. I've even got cyano on top of the hair algae that doesn't help the situation either. I'm performing 20% (40G) water changes weekly too and still no end in sight. Not to mention my polyps have terrible extension unless the MH's have turned off. Even my millis barely have any polyp extension which is not a good sign. I'm not losing any corals yet and the colors still look great on all but a few. Temperature stays at 78 unless it's really hot out then it might jump to 80. I feel like I'm doing everything right. It's not a matter of neglect. I'm working on it for a half hour to an hour a night and then probably 2 to 3 hours each day on the weekend. It's just kind of frustrating is all. I'm not worried. I'm just waiting for the reef gods to say "Ok, I think he's had enough. Now let's show him what a real reef tank looks like".

[mr_alberta]

What are you using for substrate? How are you maintaining the substrate? How old is the substrate? I'm not saying that it IS the substrate, but it's most likely a factor. Also, how old are your bulbs? Could they have shifted to a more yellow spectrum now which is causing the algae growth?

[GMGQ]

How old is the tank?

[StirCrazy]

nothing to do with actinic, while they will cause growth in algae as SAM noted it is a very slow growth as a rapid growth will raise O2 levels. your MH would contribute more in 2 hours than actinic would in 14.

you have a good skimmer and it sounds like it is working so the only thing left is that big nutrient sink we call a sand bed, HA, then Cyno, ect.. sounds like the problems I had due to my sand bed, and a familiar story among people who have removed there bed because of algae issues.

my theory is that they trap nutrients, and the algae gains a foot hold by utilizing the nutrients in the sand bed, then as the algae spreads it itself traps junk and causes more available nutrients and so on and so on.

Steve

[Jaws]

The tank's not even a year old yet. The sandbed is about an inch to two inches deep of sugar sand and was half new sand and half established sand from the local fish store. The bulbs are all about three months old so almost brand new.