My sanded is a touch under 3 which makes me want to add maybe another 40lbs . It is "live sand" I bought from pts..has shells in ir and some rubble..can I safely add more?
I don't think you'll need to use "live" sand at this point, I'd just get a 30# bag of sugar sized oolite and rinse it before you try to add it to the tank. I like to use my tank water when I do a WC for this and rinse it about 3x and dump the dirty water. I scoop the "cleaned" substrate into a 1 gal. freezer storage bag and lower it to the bottom, then slowly allow it pour out. You'll still have some clouding, but it'll be minimal. But, only cover part of the bottom, and do the other part at a later date.