hmm. I never thought about putting sand into atank like that. I dont run sand in my SW
, but I do in my large FW
Another method I have found that works somewhat decent, if prolly not as good as afihyonados's idea is to fill a small cup with the sand, top it off with tank-safe water, then slowly sink it to the bottom of the tank and literally pour the sand out.
And I agree with them, I tried to add a black sand on top of a black gravel, similiar to adding sand on topof argonite, my gravel was at the top of the substrate in a few days, as your argonite would be.
I actually set a collinder in the bottom of my tank and scooped the subtrate up and put it in the collinder, swirled it aorund some, the sand went back to the bottom of the tank, the gravel staye din the collinder and I was able to remove it from the tank.