Do you have to drill you sump if you have

Do you have to drill you sump if you have an an internal sump pump or only a external sump pump.

 

you don`t need to drill your sump , if you don`t want to

 

How will that work with and exteranal sump pump?

 

also is it possible to plug overflow holes?

 

With a external pump you would need to drill it. As far as covering a hole..I have seen it done at the lfs on some used systems. But only acrylic, He took another piece of acrylic and and used some sort of glue to seal it. I have no idea how that could be done with glass.

 

+1 on drilling for external pump.
I used a bulkhead and capped it on a 150g with two overflow holes in the bottom of the tank since I only used one.

 

Do you have a picture on how you capped it?

Internal pumps generate more heat in tank correct.

would I be able to set up some sort of reverse overflow where the salt mix containers pump water throught the bottom of the overflows out to the top?

 

No, because I don't have that set up anymore. I used something like the link I attached. I put teflon tape on the threads and screwed the cap on tight. Never had any issues with leakage. You can pick up a FPT cap at your local hardware store.
Cap Fitting - FPT

Yes internal pumps can generate more heat because they are always in the water. External pumps get warm too but the water is only there for a breif period.

 

comon, Ted.. why would YOu have to drill it? Those external pumps usually have the suction, so just have a pvc over the edge in the sump and that is it, the sump will suck the water up...

If not, then the other option is to place,the external pump, lower than sump and using siphoning method suction the water...

 

The straighter you can make your piping run on the suction and discharge sides the better off you are. No need in creating more pressure loss which is what will happen by not drilling.

 

Are internal pumps louder than external?