The Red Sea MAX e170 with a Eshopp Nano sump underneath. I have two pumps running, one in return chamber in sump and the circulation pump in rear of tank. I only have one drain tube that has a gate valve. I dialed in the valve so it won't gurgle and also won't raise in the overflow section of tank. I keep a steady water level in tank all day and evaporation only affects return chamber in sump.
The conundrum-
When I add water to the return chamber to make up for evaporation all the water added just raises the Overflow section of main tank.
So I tried to install an ATO and placed the sensor right above the water line to watch to test that the ATO fill and stop. It filled to sensor height then when the water level fell, due to the stated conundrum, the ATO refilled to sensor and then water falls and then ATO fillsover and over.
Why can I not fill the return chamber in sump without it being pumped into the tank?
The conundrum-
When I add water to the return chamber to make up for evaporation all the water added just raises the Overflow section of main tank.
So I tried to install an ATO and placed the sensor right above the water line to watch to test that the ATO fill and stop. It filled to sensor height then when the water level fell, due to the stated conundrum, the ATO refilled to sensor and then water falls and then ATO fillsover and over.
Why can I not fill the return chamber in sump without it being pumped into the tank?