Nate,
maybe just one i think we have enough. Ken is bringing a couple and I have a large ice chest and garbage can. We definately need a pump and hose to pump water back in tank. The fresh salt water feeds right from a plumbed in resivoir.
I have 55 gallons of salt water made and another 60 of fresh that can be mixed,although I think a 40 or so % water change will be enough.