A freind gave me a complete co2 system.tank regulator w/solenoid ph controller bubble counter and reactor. I dont like the idea of pumping water out of back into the tank (had a few canisters leak) plus all the other stuff in the tank. What are the ccobncerns if i just pump the co2 into the tank? Ive never (prob never will) test water so i havve no idea what ph does. What are the concerns of just pumping in co2. I have a good light on the 75 gallon tank. Its planted with dirt and doing well. I found someone who has seeds for a few erio sps that need co2. Any and all thoughts are appreciated. Also my regulator leaks so i ll have to replace it if i cant fix it if anyone has one to sell.