Hello, Although I do not own an Octopus yet, I hope to learn a lot from this site and hopefully own an Octopus in the future... But there has been a question on my mind for some time now, and I think the best way for me to come to a decision is to ask for advise and other opinions Regarding the use of Reverse Osmosis water, I am wondering if it will be worth while to BUY a RO filter for home use? And if so do they HAVE to be hooked up straight to your tank, or can you just filter water and save for future use? Or is it better to buy RO/DI water from the store? Does anyone own their own filter? I have a 90 gallon tank and I am planning on using a Sump as well as an additional back up reservoir with an auto top off controller. And from what I understand it's really important to use RO or RO/DI water?... Also, is it better to get a Protein Skimmer that is overkill for a 90 gallon? I would really appreciate some advise. I am terrible with making up my mind! Thank a lot.