Stupidly i filled up my aquarium with tap water (i know i feel like an idiot) and i bought a 20 gallon tank instead of a 30 gallon tank the guy told me that if i wanted to get a 30 gallon tank it would cost me around 1000$ as aposed to 450$ Is there ANY way that a bimac could live in my tank? If it is possible to keep a bimac in my tank would i need a protein skimmer? I thought i should drain my tap water and fill it up with RO water. Would this do anything bad to my tank or fish somehow? and if i can do this should i leave the substrate and rock work in there? Also, i would like to know if im going to need a heater or an air pump? What temperature does the tank need to be? Also, the guy gave me this stuff called "cycle" it is said to "keep aquariums healthy and rapidly mature new aquariums." He told me to put half the bottle in at first and then 2 tsp daily. Should i use this stuff?