Originally Posted by
DSkidmore
I stand by the statement, on a pure cost basis. If you're paying 33 cents a gallon and using 5 or fewer gallons per week, or paying 50 cents a gallon and using 3 or fewer gallons per week, you are better off buying the water than filtering. (I found a cheaper unit after my initial analysis that said I'd need to use 14 gallons per week to make the unit pay for itself, so I will be getting a filter for my 75 gallon.)
Unless you're having some sort of emergency, you can wait a bit longer for the store's water delivery. Even if it was an emergency, and you start running your RO/DI now, it will take several hours to get the gallons you need, and you would actually save time running around finding a store to get water. In an emergency, I'd use the grocery store's distilled water, especially if it was for a QT situation. (Yeah, I'd worry about trace copper from copper distilled water in the main tank, I'd only use it that once for the emergency and hope any trace was well dilluted.)
I am currently buying my water. I agree it's a pain. I buy a couple week's worth at once so I don't have to go every week. I am lucky enough to live in an urban area, there are 3 walmarts within easy driving distance that have RO machines, and countless grocery stores that have RO or distilled water on the shelves. If you only have one option near you, it might change the story in your case.
https://www.saltwaterfish.com/vb/showthread.php?t=170278
Speaking of that other thread, no-one answered my question: how often do you change your filters? Do you do it on a timed basis, or on the TDS meter results? I hear you can test between RO/DI to make sure the RO cuts the TDS to 10%, and after DI make sure TDS is 0-2?
Not trying to beat on you Dskidmore, but in an emergency is the key....You never know when that might be, and the smart hobbyist always keeps a couple gallons; me personally 50 gallons of pure RO/DI water ready to go at the moment incase that emergency arises...Not saying you have to keep that amount, but we all don't just sit idle and fire the dang thing up at the last moment......I run my RO/DI constant. Has automatic shutoff, and when I do the water change I usually wait a day or 2 before I start the next batch and this allow plenty of time for the temp to adjust and proper aeration and mix of saltwater....Maybe anal, but I'm always prepared....
Your other question about when to change your filters is easily done with the use of a TDS meter...You can get hand held units cheap and you can buy plug in inline units as well...With the dual plug in units you can measure the quality of water coming in and also the quality of water exiting the unit....When you see the exiting number change it's indicating to check the filters........
. Its time for a RO unit. Can someone please list 3 good units that i can look into? I have researched some but id like some opinions from experienced users. I dont need anything extreme. I only have a 46 gallon tank and i change about 10% weekly.
