# DIY Cement background not getting clear



## BrunoZA (Jun 19, 2016)

I just finished building my first ever fish tank from scratch! I thought I would then just make the styrofoam/cement background and I would be one step closer to getting my tank cycled. However, I have filled and drained my tank around 7 times (it is a 55g tank) but my water still seems quite cloudy. Is this normal? How long does it usually take for a typical cement/styrofoam background to become inert and stop clouding the water? I followed instructions online and started with a thin layer and gradually added two more thicker layers with 24 hours between coats.


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## Mcdaphnia (Dec 16, 2003)

How long did the cement cure before being submersed? Try a Diatom filter to remove the cloudiness. Vortex is one long time brand. If the cloudiness repeatedly comes back, then the cement may be breaking down because it is a type of cement that does not cure underwater. Some types require oxygen from the air to cure. Hydraulic cements can use the oxygen in a water molecule or bring a source of oxygen along in their formulation.


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## SrsSarcasM (Jan 28, 2016)

What filter are you using for this tank? Just that tiny little internal one? If so there probably isn't enough flow to adequately collect all the suspended particles. How fine is the filter media inside that filter?

Also you can get a sort of chemical, I can't remember what it's called, that coagulates fine particles into larger particles that can be removed with a filter.


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