Sand?

I also use pool filter sand in all my tanks (26 and counting) and I love it. I also chose it over regular sand because it is crushed quartz and won't raise your ph.
 
FWIW, my favorite way to rinse sand is a wheelbarrow. rinse, agitate, dump water...repeat as needed.

with pool filter sand 1 rinse is usually enough.

play sand or all-purpose sand may need 3-4 iterations.
 
I just bought some pool filter sand myself for my new tank projects. 50 lbs. for $11. Not too shabby, especially since I got ripped off when I paid $70 for 40 lbs. of Eco-complete.

I'm gonna give the pool filter sand a try.
 
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