plugging bottom holes

i picked up a 75 drilled, and my dumbarse didnt realize the overflow box is not in a desirable corner, so i want to re drill it, and move the overflow,

im going to re drill a 75 gal, has anyone ever sucessfully, or unsucessfully
closed up or plugged 2 bottome holes in a tank?
if so, how did you do it?
im thinking a good sized piece of acrylic, i have some 1/4", and a real good equal smooth layer
of silicone under it, let it dry reall good,
and maybe an equal piece on the bottom
what do you think?

 

I used a ceramic floor tile. Ran a bead of silicone around the hole and another around the edge of the tile then placed the tile over the hole. Never leaked. The acrylic should work also.

 

Well the person that owned my drilled 90g before me sealed the holes with thick slabs of acrylic. They seem pretty effective since I have yet to be able to remove these darn things.

 

okay, great! this is what i needed to hear from my
brother psycho reefers!!!
we all gotta be nuts to be in this hobby!
wife says im more addicted to this then my harley or
former crack habit. lol (just kidding, never did drugs, that i'll admit to) lmao

ok, ima drilling!!!!!!!

 

If the tank is glass I would suggest you use a square of glass to plug the hole. Then silicone it in place. Silicone doesn't bond well with acrylic, and could fail over time. Glass bonds much better. If the tank is acrylic, use acrylic and get some weld-on and you're good to go.

 

i agree with coylee. silicone doesn't make a bond with acrylic. glass is the most recommended for establishing a true bond.

 

thanks guys, i actually have a perfect size piece of 3/16 glass i could use,
but now i might go a different route.
just cleaned this tank and sump and some other stuff,
and thinking of putting it on the NJReefers site for trade for a good
overflow box and mag7, im really dreading breaking down my tank, that is estblished
and healthy.

i got some options, and im going to weigh them all now

thanks and i'll keep youse posted

 

I have always just put in a bulkhead and used a cap on the end of it, You can actually flip the bulkhead upside down so that the part that would normally be inside the tank is on the outside that way the tank still sits flat

I have done that more times than I could count and just drilled the tank where I needed holes drilled