New tank stand

[clownchick22]

The tank seems to be leaking!
We have had water and sand in it for a week and it seemed ok, but since adding the salt 2 days ago there was a bit of salt/water leakage on the side. I had bought the tank second hand from a guy that works at the pet store. I had even re-calked it myself over with 100% Silicone.
I've cleaned the tank where I spotted the possible leak... and put a paper towel there to be able to tell... so I am going to check again in the morning to see if there is anymore leakage...
I'm so frustrated! I was going to buy my live rock this week, but now it looks like I might be saving for a new tank and have to re-build another stand!