I don't know what I was thinking. I am building a custom WC setup for fun and I was trying to do it as cheap as possible. I built my own custom res using a 1 gallon container. It's a nice design, but the water into the res is towards the top. A while back I bought MCT-40. I bought 32 oz of it. That's 1/4 of a gallon, so it obviously won't fill up the entire thing. It says it's premixed and ready for use as is, so if I dilute it with distilled water, will it still act as a good anti-fungal/anti-corrosive, or should I suck it up and buy something else? Buying 3 more of these is out of the question. I can't justify the 60 extra dollars.