Overflow into sump

Hi there,
Well after using various other filters I have decided to build a sump for my tank. I would like the water leading to the sump to overflow in some way, and not have to be pumped into the sump. The glass is about 9mm thick, and I have no idea if there is a way to cut the glass near the top so as to add a groove for water to overflow. If there is a way or some other option, I would really like to know, or is this suicide on an existing tank?

Thanks,
Kev.

 

snobee if you give me till tomorrow, ile post pictures off a overflow box I had made. Cost me R275 but it will pump water from the tank into the box and then from the box down to the sump, which then pumps back via a pump. Good method if your not wanting to drill your tank like me.

 

The easiest way is to get a hang on overflow box, otherwise the next best would be is to drain the tank and build a internal overflow.

 

Going be a mission to build an overflow section, but it is the only way I can think of if you want to use gravity rather than a pump.

Size of your tank is also going to determine if is worth the effort of draining the entire tank and removing inmates etc. and making the mods.

You would need to drill the tank's base for the outlet

 

There are 2 ways to do it, you can dril a 50mm hole through the glass - this is cheap but very risky. The other way is to get an overflow box, this is quite expensive but the safest way. Reef Octopus makes a nice one

 

Thanks guys. Ok, I will wait and see what Storm posts. Though I guess the overflow box is the easier option whichever way I go? If I use a two pump system, I am dead scared of having the two pumps out of sync, etc, and the overflow being too much for the sump.
My other option which I guess no one does, is to not risk drilling into my main tank, but the sump... and then raising the sump higher than the tank, so gravity allows the water to flow from the sump. We only have one Marine Pet shop in my area and they don't have an overflow, so I will see what Storm posts. Anyone know of Pet Shops that may sell overflows in the Cape Town and surrounding areas?

 

Btw, I saw a pic here: Reeftek - Reef Octopus Overflow box unit of a commercial one. Can someone explain the physics behind the overflow box in general, especially with respect to the need for the pipe/tube above, and does the water just start flowing through the overflow or does one have to "start" it in some way?

 

To get it flowing you need to prime it first. The pipe going down to the sump needs to be under the water in your sump. If you get a power outage you won't need to prime it again.