Ok, so heres the deal. I currently have a pre-drilled overflow 90 gallon tank (4ft x 18 in x 2 ft) with a 7 Silver Arowana and a 7 Tiger Oscar. (Dont worry, Ill be upgrading to a (8ft x 2ft x 2ft) 240 gal or possibly a (8ft x 2ft x 30in) 300 gal for my Aro sometime this year, when I remodel the house and throw out some old furniture to make room 
) Anyway, I modified the bulkheads of the overflow intake and output to fit a canister filter and its currently connected to a Fluval 405 which I believe has a flow rate of 340 gph. The problem with this is that on a normal overflow tank, right when the water level reaches the top rim of the overflow, it gets drawn into the overflow and then into a sump solely by gravity. Since I do not have a sump connected, the flow rate into the overflow is the flow rate of my canister filter and this causes the water level to be higher than the edge of the overflow in the tank thus negating most of the water being drawn into the overflow. The water merely swirls around near the top of the overflow. Debris and particles are still being drawn in, but not as fast as I would like so Im wondering if the canister is cleaning at its full potential. Also Im worried about the canister because once the water level hits a certain point that is still over the top of the overflow, water doesnt seem to flow into the intake tube because it is a bit too high, due to the modification I did
and the Fluval just craps out 
. Im worried that if that point is reached while Im not home, it will burn out the motor of the Fluval, possibly starting a fire. The best case scenario would be that the Fluval will burn out, no fire, and I have to buy a new one. With that said, Im debating whether or not to get a 20 gal sump and hooking that up to the overflow instead and properly connecting the canister filter with the parts it came with. Or should I just use the sump and forget about the canister, or leave everything the way it is now? I also have a 170gph powerhead sponge filter in the tank too if that helps your input any.
Also if you guys think I should get a sump, are there any recommendations? I was thinking about possibly getting a Megaflow or a Tidepool II. I dont have the resources or the skills to make my own.
) Anyway, I modified the bulkheads of the overflow intake and output to fit a canister filter and its currently connected to a Fluval 405 which I believe has a flow rate of 340 gph. The problem with this is that on a normal overflow tank, right when the water level reaches the top rim of the overflow, it gets drawn into the overflow and then into a sump solely by gravity. Since I do not have a sump connected, the flow rate into the overflow is the flow rate of my canister filter and this causes the water level to be higher than the edge of the overflow in the tank thus negating most of the water being drawn into the overflow. The water merely swirls around near the top of the overflow. Debris and particles are still being drawn in, but not as fast as I would like so Im wondering if the canister is cleaning at its full potential. Also Im worried about the canister because once the water level hits a certain point that is still over the top of the overflow, water doesnt seem to flow into the intake tube because it is a bit too high, due to the modification I did
and the Fluval just craps out . Im worried that if that point is reached while Im not home, it will burn out the motor of the Fluval, possibly starting a fire. The best case scenario would be that the Fluval will burn out, no fire, and I have to buy a new one. With that said, Im debating whether or not to get a 20 gal sump and hooking that up to the overflow instead and properly connecting the canister filter with the parts it came with. Or should I just use the sump and forget about the canister, or leave everything the way it is now? I also have a 170gph powerhead sponge filter in the tank too if that helps your input any.Also if you guys think I should get a sump, are there any recommendations? I was thinking about possibly getting a Megaflow or a Tidepool II. I dont have the resources or the skills to make my own.
