Fill my Hole :(

[Magma]

My 75gal has a leak at the bottom front right in the middle, it was fine untill I started to fill it with fresh water just to get the filter going, but once it was 3/4 of the way full I had a leak going on.

Now not having done any silicon job before I would love it if someone could come over and help me re-seal this I just need to know what kind of silicon to buy and any other tools needed and should be good to go.


Also the tank already has black silicon on it, anyone know where I could get some more of that? or should I go for clean stuff now to patch it up?