Pool filter sand

Humblefish · Jul 12, 2017

I've been using this stuff in (low light) holding tanks for years:

https://www.quikrete.com/pdfs/data_sheet-sand-poolfilter.pdf

http://www.homedepot.com/p/Quikrete-50-lb-Pool-Filter-Sand-115350/202314677

I get more algae growth than I would care for, but I assume it is from the silica. I get it under control after awhile.

What I'm curious to know is if anyone is using pool sand in a reef tank with strong lighting, and if so, how is it working out for you in the long-term?

clsanchez77 · Jul 12, 2017

I have used it in the pasted as a refugium substrate for the finer size and heavier particles. I now use miracle mud which I believe is mostly 'fertilized' silica sand, despite manufacturer claims. It is primarily composed of silica dioxide, which despite rumors, does not break down within the parameters of a reef aquarium. Like all commercial products, there is some degree of purity that is not stated and being a natural product, it is fair to assume the impurities could include soluble forms of silica, phosphates and/or other minerals. However once these are gone, there should be no feeding silica to the tank. Maybe why you seen an initial bloom but not a long term one. The biggest issue with it is it gets trapped in the glass scrapers and easily scratches glass.

If you recall on LARC, I gave a way a used 90 gallon tank that was heavily scratched on the front glass - it was because I used silica sand in the tank when it was setup as brackish in between my reef tanks and it was relentless on the glass. To me that was a far bigger issue than fueling algae.

Humblefish · Jul 12, 2017

clsanchez77 said:
If you recall on LARC, I gave a way a used 90 gallon tank that was heavily scratched on the front glass - it was because I used silica sand in the tank when it was setup as brackish in between my reef tanks and it was relentless on the glass. To me that was a far bigger issue than fueling algae.

Were you having this issue mainly from using magnet cleaners? Or was the sand getting in your algae pads as well?

clsanchez77 · Jul 13, 2017

Humblefish said:
Were you having this issue mainly from using magnet cleaners? Or was the sand getting in your algae pads as well?

Magnetic glass cleaners, when the sand was in the DT. Again, in my brackish tank, not reef. I have never used it in a reef DT but I have no reservations about doing so, other than just not natural appearing.

Humblefish · Jul 13, 2017

clsanchez77 said:
Magnetic glass cleaners, when the sand was in the DT. Again, in my brackish tank, not reef. I have never used it in a reef DT but I have no reservations about doing so, other than just not natural appearing.

I wonder if there's something in pool sand which attracts magnets. Maybe aluminum or some other metal?

I seem to remember a similar problem (attracts magnets) with certain types of black reef sand.