My algae knowledge must be lacking...

[Gauge]

For those of you who might remember me, it's been a while. I've upgraded from the old 42 hex to a new 92 bow-front. I've got 110 watts of PC actinics, 250 watts of 10,000K MH, 170 lbs of LS, 100 lbs of LR, just a few small fish, and some inverts. It's running on a refugium of my own design with an Aqua-C EV-180 (if I remember correctly) skimmer and a Mag 5 running the skimmer. The return pump is a Mag 7.

So, anyway, here's my issue. I have a golf-course-looking patch of hair algae all over my rocks. That's fine. I know how to fix that. Simply keep the nitrates down, the phosphates down, and have a cleanup crew, right? Okay. I was without a cleanup crew until last week, so they're now digging on the rocks and making noticable progress. Problem solved, right?

Wrong. I have cyano all over my sand. Here's what's wierd about it, though. First of all, my nitrates are about 15 and my phosphates are about 0.25 at most... probably lower. Secondly, when the actinics come on in the morning the sand is pristine. It's 100% white with not a trace of red slime. Then, after 60 minutes it's covered with brown film. After that the hallide turns on and it just gets worse until the end of the day. Then, the next morning, it's clear again. What the heck?

Now, my nitrates are good, my phosphates aren't very high, my lights are backed down to like 6 hours a day (6 actinic with 3 hallide in the middle), and I don't know what else to do. I don't want to get a sand sifter simply for the sake of keeping my sand from growing over with cyano. I'm at a loss. What else needs to be done? Temperature hangs around 80-81, if that matters, and my SG is about 1.022.

Is there something that I haven't yet been educated about in this area?

[malkore]

using a protein skimmer?

[Gauge]

It's running on a refugium of my own design with an Aqua-C EV-180 (if I remember correctly) skimmer and a Mag 5 running the skimmer.

[ellisz]

How new are your bulbs? Could try some phosphate sponge in the sump to see if that helps.

Cyano is tough sometimes. I have tried to up my flow in my tank to help combat it but this is tough on some of the softies.

HTH

[quarryshark]

Actually a PO4 of .25 is enough to feed a cyno outbreak, I agree to run a sponge and also check your source water for PO4. Does your RO unit have a DI stage?

[Gauge]

I had heard that 0.25 ppm PO4 was not bad, but I did doubt what I was hearing since I had eliminated so many other possible causes. If you think that it is enough, then I'll take your advice and get me some PO4 sponge.

I buy my RO from different sources. I believe they all have a DI stage, but I'm not 100% on that. I will try to test them all and then stick to one souce in the future just to make sure that I can eliminate that as a possible source.

What other sources of PO4 can I look for? I don't over feed, but I use a lot of different foods. Occassionally I feed live (rarely, though), sometimes I use frozen (multi-packs w/ Zoe and Garlic Xtreme), but usually I use flakes. Any other possible sources? That PO4 sponge is expensive, so I don't want to use it after this if I don't have to.

Also, is it normal for cyano to A) grow as fast as I was describing, B) disappear overnight?


Thanks for the help!


** EDIT: Forgot to mention that my bulbs are 3 months old, as is this tank setup. **

Originally Posted by Gauge

What other sources of PO4 can I look for?

The hardest one to get rid of and the one that cannot be tested for, organic PO4. If you detect anything with your PO4 kit, then you will have an abundance of organic PO4. The higher the inorganic the higher the organic levels. They form a chemical chain causing one to breakdown and another to form in an endless succession. Even when doing everything right and ensuring not to overfeed, the amounts can build naturally over time. It's just one of those things.

Best way to remove it is with a non-aluminum oxide based PO4 sponge as has been suggested.

Cheers
Steve

[quarryshark]

Originally Posted by Gauge

.

I buy my RO from different sources. I believe they all have a DI stage, but I'm not 100% on that. I will try to test them all and then stick to one souce in the future just to make sure that I can eliminate that as a possible source.

I would check your source water wherever you get it from.
Food for thought. If you can swing it, may want to consider your own RO. This way you can have some control over your source water. I know they are expensive, but you have to buy the water anyway.
The DI is the important component in cyno control. It is this 3rd stage that removes the PO4 from the water. Many RO units come in a 2 stage and will not reduce the PO4 in the source water. I purchased a 2 stage and had a major cyno problem until I added a DI stage. This was IMO the major reason I was able to get it under control. I, like you had tried everything else.

[Gauge]

Also, is it normal for cyano to A) grow as fast as I was describing, B) disappear overnight?

Anyone?



Oh, and I bought some PO4 sponge last night. We'll see how things look when I get home. It said it would work within hours.

[quarryshark]

Originally Posted by Gauge

Anyone?



Oh, and I bought some PO4 sponge last night. We'll see how things look when I get home. It said it would work within hours.

Mine came on rather suddenly, but it took a couple of weeks to disappear. It seemed to turn a brighter green first and then disappeared.
Of course I had a good amount of water volume to clean up. In a smaller system it may happen faster, but in your 92 gallon, I would not expect it to happen overnight.

[Gauge]

...when the actinics come on in the morning the sand is pristine. It's 100% white with not a trace of red slime. Then, after 60 minutes it's covered with brown film. After that the hallide turns on and it just gets worse until the end of the day. Then, the next morning, it's clear again. What the heck?

I think you misunderstood my question.

[quarryshark]

Don't know, did not have that experience. Sorry...

[MarineFlake]

Gets better overnight..Could be your clean up crew. Are you currently using a sponge of any type? I have plenty of algea and some cyano, however, I have never witnessed it simply disappear over night and reform in the morning. The only other thing I can think of, and this is a long one, maybe there is some growing in some unseen spot, loosening up and dumping on the sand. Be nifty to see a pic of before and 60 minutes after..

[Gauge]

I can arrange that. I'll have to change the timing on the lights so they come on after I get home from work. I am usually only able to notice this on the weekends.

There is nothing unusual about the way the algae is behaving. Both cyano and diatom algae are quite photosynthetic and like anything that is, stretch's out when the light is abundant and recedes when it's gone.

Algaes of any kind need two primary things to survive, light and nutrient. Since this is a reef tank starving the algae of light would be counter productive to coral health. It would also be a shortlived solution since it will slow down the use of the nutrient and do nothing for it's elimination. The only thing you can do otherwise is starve it of nutrient. Diatom is mainly fed from silicates which would come in through the water source. I would definately suggest checking that.

Cyano is mainly fed through organic and inorganic PO4. That can come in through many sources but primarily foods fed to the animals. Cyano also has the ability to manufacture it's own nutrient to a small degree making it much harder to remove. Cyano can process these nutrients so fast in fact that if you add foods it can easily sorb the nutrient so quickly the inorganic PO4 may never show up when testing. The best means to eliminate cyano is through the use of non-aluminum based PO4 granular sponges. It will remove all forms of PO4 and then work on removing silicates thereby killing both problems. Eliminate the PO4 and you eliminate the algae.

Cheers
Steve