What is this algae in my tank that won’t go away.

[whitasm]

Hello, I’ve had my tank up and running since the end of August. Around October I started seeing what I thought was diatoms. They started slow then exploded and covered my rocks and sand. The trochus snails are eating it which is making me believe it’s diatoms but at this point I would think they would be out of silicates to feed on. It’s getting stringy and not really going away. Can anyone help me identify this annoying algae. Nitrates are about 10-15 after just resting and phosphates are undetectable based on the salifert test.

 

[Lavey29]

Still looks like heavy diatoms. Does it blow off the rocks? Your tank will go through a variety of ugly phases the first year.

 

[whitasm]

Still looks like heavy diatoms. Does it blow off the rocks? Your tank will go through a variety of ugly phases the first year.

Yeah it’ll blow off for the most part of I give It a big turkey baster blow. I can easily scrub it off with a toothbrush and that’s what I’ve done for a while and then just decided to leave it and let it do it’s thing because it all came back in about 3 days.

 

[Lavey29]

Yeah it’ll blow off for the most part of I give It a big turkey baster blow. I can easily scrub it off with a toothbrush and that’s what I’ve done for a while and then just decided to leave it and let it do it’s thing because it all came back in about 3 days.

Check your RODI for residual silicate. I had some in mine so I always have a light dust of diatoms here or there on my sand.

 

[whitasm]

Check your RODI for residual silicate. I had some in mine so I always have a light dust of diatoms here or there on my sand.

That’s one thing I don’t have is a TDS meter on my filter. I assumed I was getting bad diatoms because of my deep sand bed and dry rock. I guess it’s been a little over a month now since I first noticed it.

 

[Lavey29]

That’s one thing I don’t have is a TDS meter on my filter. I assumed I was getting bad diatoms because of my deep sand bed and dry rock. I guess it’s been a little over a month now since I first noticed it.

I'm sure you are but if they linger past a month or so then you may have residual silicate getting into your tank like I do. Verified via ICP test on my RODI.

 

[whitasm]

I'm sure you are but if they linger past a month or so then you may have residual silicate getting into your tank like I do. Verified via ICP test on my RODI

Gotcha. And why are you getting that? I got a new rodi system and everything. I did see that it could be PSI causing it which I am using a bathroom sink so maybe that’s it?

 

[Lavey29]

Gotcha. And why are you getting that? I got a new rodi system and everything. I did see that it could be PSI causing it which I am using a bathroom sink so maybe that’s it?

The DI filter isn't catching all the silicate as it works its way through the process. I'm trying out a spetrapure silicate buster filter there now. Apparently silicate is a difficult element to remove completely in the RODI process but out tanks need some silicate anyway.