So I set up a new Waterbox AIO 20 cube and I had a disaster. So I set up my Tunze 3155 ATO sensors and hose in the 3rd return chamber. Everything was fine for a few days, then the display and first 2 chambers overflowed. The ATO did not fail and the return chamber stayed at the exact level as the ATO sensor. The water level in the return chamber kept dropping so the ATO turned on until the water was at the proper level. The tank is brand new and I am currently cycling it. I decided to go no sand and just rock work. I just filled the tank and watched as the return pump lowered so ATO filled it up, then 30 seconds later it dropped and ATO filled to sensor and it kept repeating as the tank was filling and filling and filling. Does anyone know what’s going on? It’s a brand new tank straight from Waterbox. This thing terrifies me