Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
Get a # 20 or #30 grade density inert quartz-based silica pool filter sand, preferably from a reputable pool or spa supply store, or from a big box store, but if from the latter, make sure it is true pool filter sand - nothing else in substitution. Cost should be not more than $15., or less, for a 50 lb. bag.
Avoid any type of 'play sands"!
I've used above type of PFS for years in my discus & other tanks - very clean with little or no dust or dirt - needs little or no rinsing, won't cloud the water, will not free flow up into the water column when disturbed, so no chance of clogging up the filter - easy to keep clean and will not get siphoned out when using a store bought pool vacuum tube hovered approx. 1" above the sand.
Layer the sand no deeper than 2 & 3/4" to 3" at the rear where most plantings will be, and as thin a layer as possible - say no mote than 1/2" or so at the front of the tank.