tank drilling/overflow

thresher9

thresher9

Member
I'm getting a new tank and not sure which will be better, an overflow box, pvc overflow, or drilling holes. So many choices!
And for drilling holes, how many holes would I drill, how big, where on the tank to drill them. I know you can have them on the bottom or at the top water level, but I'm not sure how the bottom one really works.
The tank will be a 46 gallon and i'm getting a 20 sump. Any help would be awesome!
 
bang guy

bang guy

Moderator
Drilling holes is hands down the better option if you want a sump. Nothing else is even close.
The location depends on design. I personally avoid the bottom panel because most are tempered and I'm not comfortable drilling tempered glass. I would recommend buying a pre-drilled tank.
That said I would do as low as possible with a standpipe or an internal overflow.
 
thresher9

thresher9

Member
Well I've look around a lot and there doesn't seem to be many pre drilled tanks. So, looks like i'm doing it myself! With the bottom being drilled, I've read that the bottom glass will break easy. But is it better to have the hole on the bottom or near the top?
 
S

saxman

Guest
The only reason a tank bottom might break more easily when drilled is because some tank bottoms are tempered, and tempered glass can't be drilled.
Another thing you need to consider is to be sure and give yourself a 2" margin between the hole and the edge of the glass panel, and be sure you leave enuff room inside the tank for the flange of the bulkhead to fit without hitting the panel.
 
snakeblitz33

snakeblitz33

Well-Known Member
Before you make a rash decision and put a hole in your tank... research a little more. While putting a hole in the lower back panel has it's benefits, so does other designs. Look into "coast to coast" overflows, Bean Animal overflows, Calfo overflows, Herbie overflows and others. Personally, I am really enjoying watching Eric125's build on these forums. His thread is "taking a new direction" and he has recently done a very good step by step of how to do a coast to coast overflow.
Why I personally like the design is how quietly it runs and how redundant the system is. Although, I also agree that it is perhaps a bit overboard for a 46g.
 
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