Somebody Stop Me!!!

[MotoFish]

I have a small area around the return coming back into the tank where the water is able to leak slowly back down to the sump. Causing me to have enough water in my sump that it could potentially overflow.. I tried silicone once already and it still leaked down over time. I want to try it again.. But this time I want to use some black silicone. It's made by DAP.. There was 4 different kinds at the store.

White - Kitchen and Bath
Clear - Marine Use (didn't say aquarium safe)
Black - Automotive (high heat)
Another Clear that said aquarium safe.

I bought the black..

They all say 100% Silicone...

why can't I use the black? I intend to let it sit exposed to the air for more than the 24 hour fully cured time they say.. If you allow it to fully cure, why would it not be safe?
What is the difference between the black and the Aquarium Safe one? THey all say they are 100% Silicone... Am I missing something? I'm going to use the black unless someone can give me a good reason not to..

:conf44:

 

[Tikalize]

I have used GE Silicon 1 Window & Door. Whatever you use just make sure that it dont say mold & mildew protection. Other than that i would not have a problem using it. Just my two cents

 

[sklywag]

If you're going to shut down for 24 hours. Spend a little longer and get her done.

 

[goth2o]

What exactly is leaking,a bulk head, or do you have an internal over flow seam leaking.Is your tank acrylic or glass.