clear water yet cloudy under light

[ashepler]

We have a 75g planted tank with roughly 20 smaller fish. It's been running for 6-8 weeks, cycled, no problems etc.

The tank is pretty clear except when you're sitting next to it looking up towards the light. There appear to be tons of really small particles that are not being filtered out by a fluval 405 containing the prefilter, carbon, biomax and polishing pads.

What could be causing this cloudiness?

A view of a portion of the tank:

a poor attempt to capture these particles:

Thanks in advance for any ideas

 

[Johnny Tuttle]

It looks like a beautiful tank set-up.

Is there any chance this is the start of some plant matter decomposing, algae, or detritus from your ammonia source for your cycling?

 

[ashepler]

It is possible. My first thought was some sort of bacterial bloom, but aside from a few new plants there hasn't been much of a change lately.

You may be right about the start of some plant matter decomposing. Now that I think about the few small plants were added a day or two before this cloudiness started.

I guess the other possibility might be my DIY CO2 stopped working a couple weeks ago. Perhaps this is the start of an algae bloom.

 

[Johnny Tuttle]

If that's a telephone pole I'm seeing in the background (meaning, I'm looking out your window through your tank), then there's a good chance you're going to have algae sooner than later.

The other thing I notice in my tank is that even with a hood, it will get atmospheric dust in it. I noticed a hair in it the other day. You might just be seeing the conglomeration of a few weeks' worth floating around, assuming you've not done PWCs during the planting and cycling stages.

 

[ashepler]

If that's a telephone pole I'm seeing in the background (meaning, I'm looking out your window through your tank), then there's a good chance you're going to have algae sooner than later.

This tank is viewable from all four sides, dividing our living and dining rooms. The vertical line is actually part of a split pane window 15 feet beyond the tank. That is a south window, but there is a 12 porch overhang beyond that and two huge shade trees so there's no sunlight hitting anything in that room.

I've got my CO2 working again so hopefully that will help prevent the algae possibility..