Is it safe to replace my rockbed in my aquairum with silica sand?

Question

My dad works at a building materials company, and he is able to get silica sand for me for no cost at all. But what I am worried about is if there are any chemicals in the sand that will harm my fish or raise my pH level.

Answer 1

As long as it's untreated silica, it's fine.  Silica sand (mostly silicon dioxide) is entirely inert and almost entirely insoluble, so there's no threat of it providing silicate for diatoms (a type of algae).  Just make sure you rinse the sand VERY well in a bucket until the water runs clear-- the dust will leave you with a permanently cloudy tank, otherwise.  Also, when adding it to the tank, do so gently and turn off the filter.

EDIT: As I said, silica is INERT and will not affect the pH as calcium carbonate substrates like crushed coral or dolomite would.

Answer 2

nosoop is right but also, the sand will raise your ph, if you have african cichlids from lake malawi thats great  its perfect for them with the high ph, but you will have to use chemicals that you get at the pet store called "ph down" to lower the ph if not. it will depend on the type fish you have.. ,

and like nosoop said be sure to wash your sand , and put in tank slowly, and keep the pump turned off til your sand has settled, i ruined my pump by not doing that..