It sounds untrustworthy to my. Fish tanks are alot of weight and need a stand that can hold it all. A 30 gallon tank is about 300 pounds of water, not including the rocks, plants, fish..ect. A wobbly stand I would not take the risk of putting a fish tank on. I bought a stand from wal-mart or my 55 gallon and it does not wobble at all, its completely sturdy.

If I were you I wouldn't take the risk of filling the tank up on that stand...if its molded to the wall it may be a little more trustworthy, but not fully trustworthy.