I don't have a RO unit right now, so I plan on just using tap water that will be purified via a solution like Aqua plus or the like. I know RO is the best, but I can't afford it right now. Will this stuff work like it says it will? Also, will I have to add any kind of buffer to the tank before I mix the salt? I want to make sure everything it completely perfect before I start introducing an octopus.