R\O filters work like this: One hose connects to your tap (sink), screw in, if none have then need to connect outside. then 3 other tubes, 3 different colors, 1 is for bad water, 2 other is for good. You need to have the 2 good tubes empty into a bucket, contanier, something and the bad water expel down the sink or on the lawn. Now the prices work like this, the higher the price, the more gallons per day it can produce. So if you have alot of tanks and do alot of water changes you would want more GPH, I have a 25 or 35 GPH R\O and its fine for my 55 gallon, 30 gallon, and 90 gallon, I just do water changes different days for each. You can probly go as high as 250 gallon per day, but thats alot of money. 35 GPH R\O should cost about 120-150 dollars. This is the best filtration possible. It strips your water of 94-98% contaminants and minerals. Basically straight h2o. You buy R\O Right which is a jar of powder containing the natural minerals back into the water, the more you add the higher the pH. The R\O filter will bring the pH down to 4 or 5. Add the R\O mix as necassry to achieve your pH. it will come with instructions. This is what serious aquarists use. But don't be fooled it really not complicated to use, just let the water flow thru and gather the good.
EDIT: buy from Big Als Online, they have the absolute best prices, garaunteed.
Direct Link to R\O Filters
