Are there any other places to get black sand that would be safe for an aquarium other than the pricey pet store bags of black sand? Also what is the general rule of thumb for how much to buy for you tank...isn't it like one pound per 10 gallons or something like that? If you know of any place to get cheaper black sand let me know...I would appreciate it!

you come over here in my place and get a truckload, free...

no kidding aside, try to look at the hardware store or a playsand.
they are basically the same....the only difference is that: the one
sold at the pet store is screened; washed; and properly packed.
the one sold in the hardware is not but much much cheaper.

I wish I could come there and get some! haha! I've never seen black playsand anywhere though...I've kinda got my heart set on the black sand. I'm assuming there has to be somewhere that carries it...don't really wanna spend $20 a bag if I don't have to!

what is the rule of thumb? is there a calculation for square inches X number of inches thick = # of pounds???

the basic computation is that sand should have 100 pound per cubic feet.
engineering subject. however, variance is being considered due to their class
and dirt embedded in it.

How deep should sand be on the bottom...I was thinking about 1.5" or 2 inches? Didn't know if its best to keep it shallower due to the gas transfer in sand being less than in gravel. If that makes sense.

hmmm....only other black sand I can find is black beauty sand but that is actually made from iron slag so it doesn't sound that safe...wish they made a black playsand...tempted to just get regular sand but I love the look of black sand...looks like i'll be shelling out the cash for it though.

black sand is basically silica based and came from an iron materials....i am not sure
but we have been using them ever since. or maybe you are looking for a synthetic black
sand made of harden plastic....a granulated not as fine as the real sand

there are also a graded granule or grinded rocks....maybe you are referring to that

The black beauty sand is actually a sandblasting media....said its iron slag and not recommended for fish that dig alot because it can get a little sharp so I'm gonna be on the safe side and stay away from that...the aquarium sand I was looking at is the Tahitian Moon Sand which most LFS's carry and online aquarium places...

I just would have preferred to find something cheaper than that but i'm having no luck.

Search around I didn't pay an arm and leg for mine. pet smart sell my stuff at £10.99 per 1kg I paid more like £15.00 for 25kg from a fish store that deal with more customers with larger aquariums. you can find it a lot cheaper if you look but its true most shops stock small bags so its not easy.(

I did find some for like $20 for a 20 lb. bag...still more than I would like to pay but I think that is gonna be my only option right now...oh well...still love the black sand and would rather set everything up how I want than go with a cheaper option and not be happy with it.

It is worth it in the end - even if costs a bit (it cost me a fortune btw).

Tahitian is better than the Slag or Pool sand you can get - as both can cause damage to your fish (especially the slag sand).

Make sure whatever you get though is actual Tahitian - cause there are some places that simply dye ordinary sand and market it as Tahitian - will last about 5 years before the black wears off