Bro....
Is a big waste to cut off your Eheim 2222....
You intend to keep marine of freshwater ?
Your tank 2 x 1.5 x 1ft , what temp is you aimming ?
Do you know by using 4 x Micro-chiller (ice-probe) Price is higher than buying a chiller , how many electric bill cost ?
If you really wanna cut your Eheim cannister, i can help you ( FOC )