What is this?

[Rizup]

My co-worker is having an issue with his sandbed. He has tried cleaning it and this is what came back a day later. What do you guys think? Cyano? Dynoflagellates? How should he go about getting rid of it? Thanks for any help you can offer. I am sure he will appreciate it.


http://i266.photobucket.com/albums/ii258/rizup/cyano.jpg

[davewbush]

Looks like the start of Cyano. He needs to find a way to lower his nutrients in the tank. Giving us water parameters would help also.

[Rizup]

Ya, I thought the same thing. I had him check his parameters. He has been checking them over the past week each day I think, and he is measuring 0 nitrates and 0 phosphates. I thought for sure that his parameters would be out of line, but they seemed to be good to me. His calcium was a little low, but not bad.

[davewbush]

Do you know what kind of flow he has in the tank, how often he does water changes, is he using ro/di water?

[Rizup]

He is using a Mag18 for a return pump and two Koralia 3 powerheads. This is in a 90 gallon tank. I have told him that I thought the issue was with not enough water flow; he had taken out one of the K3 because he thought he had too much.

I convinced him that water changes were important and he has been doing them more frequently. I think every two weeks or so, but I think he is only doing small changes (maybe 10 gallons, I don't know).

He is using RO/DI water, but he hasn't changed cartridges since he got the unit 10 months ago! I tested his TDS and it was 4. He has ordered new sediment, carbon block, and DI cartridges that will be in this week. He has also ordered a dual inline TDS meter to keep an eye on when he needs to change cartridges from here on out.

He also told me today that he tested his RO/DI water and tested Phosphates at .5! Could this be accurate? Maybe this is fueling the bloom and would this explain why he is getting a reading of undetectable phosphates in the tank?

I got him to remove his MegaFlow sump and replace it with a 30g Breeder sump/refugium that he built. He has had this in place for a month or two growing chaeto and in the pics he has shown me, this made a big difference itself.

Thanks for the help.


Mike

[davewbush]

Sounds like he has enough flow. And changing things on the ro/di is a good thing to do also. If he has not done water changes like he should, that could of caused it. I do 10 gal a week on my 90.

[highfyre]

I get a little in areas on my sand bed that dont get good flow. I just stay on top of it and vacume it up once a week. Slightly stirring the top of the sand bed helps too, just to break it up.

[Rizup]

Could this also be caused by metal halides that haven't been changed in a year or more? To me it seems like there could be several possible causes. I'll pass your advice along to him. Thanks again.

Mike