cyanobacteria?

[NateNBeckie]

I think this is what I have in my one 29 gal SW tank. It looks black, and it keeps forming on the back glass of the tank. No matter how much I clean it, a week or less later it's back. I put a big stick airator in there to get some movement since I haven't gotten a powerhead for it yet, and they form even where the bubbler is.

I know that PO4 is the cause, but are they that harmful to the tank? Is there something I can do to control it other than chemicals?

Nate

[seaham358]

Using ro/di water will help clean up the problem over time. Using a phosban reactor works well also.

[NateNBeckie]

Ok. I just don't have the $ for a decent ro/di setup at the moment.

How about Blue leg hermits? I see they'll eat BG algae, which is a form of cyano.

Nate

[quarryshark]

Nothing that I know of will eat cyno. Many LFS's will sell you RO water pretty cheap until you can get you own unit.
Test for PO4, that will tell you a lot. You can always run a PO4 sponge for a quick fix until you can tackle the source (usually the source water).
Also get a PH, the airator will do nothing to help. The PH will produce more water movement and make it difficult for the cyno to set up.
Also, what is your feeding schedule? Do you drain the packaging fluid from your frozen food before adding?

[schoeplein]

How stable is your water temperature?

...have you tested for PO4?

As far as RO/DI water -- you dont have to buy the equipment, just get water from a source that runs the water through one. IE. The water machines in front of HEB, Wal-Mart, or whatever large grocer is in your area. Your LFS might also be able to supply you with RO'd water.

[NateNBeckie]

My water temp is very stable at a constant 79*.

I haven't tested for PO4, but I can pick up a tester. I transported the water from the guy I bought the tank from, and he supposedly used RO/DI water, but the tank had this in it when I got it. My other tank that I use filtered Pur water in doesn't have this. I just have red slime in that one that I clean once a month.

I only have the airator in there as a temp to keep the water moving, since the filter doesn't do much for movement. I'm going to get a PH in there soon and more live rock.

I generally feed twice a day. I know, too often, but I feed them very little. They generally get marine flake food or crushed shrimp pellets since I haven't ventured in to the frozen stuff yet.

The funny thing is my other tank on the same feeding schedule and everything just the bulk of the water came from a different source doesn't have this issue. It does have a PH in it, but it didn't until recently, and I never had a cyano issue. I'm going to do a 25% water change on it in the next few days.

Nate

EDIT:

Oh yeah, my other readings are:

Nitrates: 40 (time for a water change)
Nitrites: 0
Ammonia: 1.0
PH: 8.3
SG: 1.022

Both of my tanks read the same. My third tank just got set up so it is beginning to cycle.

[schoeplein]

Pur water filters are the same as Brita water filters -- all it is is active carbon filtration. It removes flavor and most foreign bacteria/rust/particles. It is not suggested that that be the only filtration that your water goes through before putting it into your tank. Carbon isn't guaranteed to remove all of the chlorine and dozens of other chemicals that come with tap water.

Your ammonia is high, as you probably noticed. Time for some water changes with RO (and any other filtration you can get it through) water.

[mastershake]

how old is the tank, also i was pretty sure red slime and cyano bacteria were the same thing, could be wrong, anyways, pretty much every new tank (less then a year old) will have a form of cyano or slime bacteria, you can usually wait them out, it may take a while, expect to see lots of different algeas and such, itll all go away with time, perfect balance in a tank takes a long time, the best thing to do is control it with siphoning so that it doesnt just take over, make sure to keep it off corals, thats the only thing it can really hurt but smothering them, id say stay away from any kind of chmical treatments, chemi clean the only one that *works* and that only prevents it from coming bakc it doesnt actually kill the stuff thats there, plus, it wont work correctly unless you find the source of the high amounts of excess nutrients and remove it, good luck

[NateNBeckie]

Well, I figured out my ammonia issue is because my tester is for fresh only. In freshly made salt water it shows the same amount as the water in the tank.

I just cleaned it all, let it settle to the bottom, vacuumed it, and did a 65% water change in it and it's still showing my nitrates at 40. Weird.

The Pur seems to do a good enough job for now. As I said, I haven't had a problem in any of my other tanks (except for the red slime). Not sure if red slime is a form of cyano. It comes in so many forms it's hard to remember what is and isn't.

Nate

[schoeplein]

Red slime is cyano. Any slime'ish material that covers the sandbed rapidly (ranging in color from light brown to deep blood red or even black) is cyano.

If your sand-bed has always been covered by this, that's not a good thing. If your back wall is covered its most likely another algae that can be consumed by snails (astrea and turbo come to mind).

I'm curious how after a greater than 50% WC you're still at 40ppm nitrates? Does your fresh salt-water test 0ppm for nitrates?

[NateNBeckie]

Well, I haven't tested as I've made it, but my other tank uses the same water and it's at < 10 ppm. I just did a 25% change in my other tank last night too.

I found that weird too. I wish I knew.

I guess I could make a gallon and see what's up.

Nate