i need the best and easy DIY sump
Clear rubbermaid tote from walmart. Find one that does not have any holes in it or if there are holes they are only in the handle area and make sure not to fill it above that point or to seal the holes with sylicon.
What ever you want but it could include a skimmer, heater and any other accessories that woudl other wise hang on the tank.
the design for the overflow
You could DIY
yourself an overflow. Check the DIY
forum for that. Or you could look around your local stores for a "U" tube overflow. These would be overflows that use a round tube in the shape of a U to pull the water up out of the tank into the overflow unit.
Once water is in the sump you will need a powerful pump to push the water backup to your tank thru a return line.