Used sand question

I've got about a 150lbs of sand from a tank that someone else took down for free. I don't know what there tank perimeters were. I Just know the tank was setting for about a month with water flow and a little light and the water looked pretty yuk.
I have a crushed coral bed right now and it can be a pain in the but.
Would the sand be ok to use or what to do to make it safe?

 

No I would not use that sand.. In concrete for a building a foundation.. Its foul and probably exhausted of all the elements that a good sand should have.. People don't understand that a good grade of sand will dissolve and its mineral content will go in to solution in the water helping to supply ca. Carbonates and many other trace elements. Get yourself some good fresh aragonite substrate as its dissolves better at higher P.H's we maintain in marine tanks..

 

what type of sand is it

HI,
If you keep the sand wash it well one say 10 pound rinse alot, I use a small coleman cooler to help this and well water,
If you have rinsed most of the detri out and its rinsing clear, I would cycle it as any new system, I don't depnd on my sand for ca or kh so it rarely ever get used Calcium can"nt dissolve above a ph of about 8 and I never get that low.
That sand may be just fine as long there's no copper been used in the tank if you want to keep inverts or corals.

I ve used home depot sand without any problems with silica , my guess it dosen't dissove that easily in saltwater
There's lots of concerns about quality of sand.
Doug