Who locally drills tanks?

[ChrisRD]

It's a 75 gallon tank.  

 

I guess there's some benefit to going either way.  Two holes is more plumbing, and if you're going with Dursos, Stockmans, etc. for silencing it's a PITA to get them working in harmony.  OTOH, two drains are sorta nice in case one ever got plugged, but personally I've not had a big problem with that in the past provided I take a few precautions with the setup.  

 

For example I like putting a lid on the overflow box, keeping the tooth spacing reasonably tight (say 1/4") on the overflow and making the box out of an opaque material (no light = no algae).  Putting an intake strainer on the inlet of the drain pipe is another option (although in this latest setup I didn't feel it was needed and didn't want to make the overflow box large enough to accommodate it).

 

Another factor in the single drain thing for me was the bit.  I already have a glass coring bit for 1-1/2" bulkheads.  I'm putting about 900 GPH through the drain on this tank (after losses) so a single drain of that size was already more than big enough.  

 

HTH and good luck with your setup. [tu]

[ChrisRD]

Doh...    ...just noticed the second part of your original question.  You can use GE Type 1 silicone from Home Depot to reseal a tank (I've done it several times).  Make sure to get the Window & Door stuff (blue & white tube), NOT bathroom stuff (anti-fungal additives).  I'm sure there are other alternatives, but this is the only one I know is safe from first hand experience.  

 

You'll notice if you read the back of most silicones sold in hardware/home improvement places it will mention that it's not for aquarium use somewhere.  With that GE stuff, you'll notice there is no such reference.  Apparently some silicones don't perform well under constant immersion conditions and some have anti-fungal additives (both of which have obvious consequences for us aquarium folks :D  ).  That GE stuff has neither issue.  

 

Just use a razor blade to strip off any old silicone and use masking tape to outline the joint prior to applying the silicone.  Apply a thick bead and run your finger up the joint.  Quickly pull the masking tape off before the silicone gets tacky.  You should have a nice, even looking joint with neat edges.

 

BTW...    ...I would drill the tank for you or loan you the bit but unfortunately I don't have my tools down here (they're at my house up North) - sorry.

 

Have fun!  [tu]