Don, My MM80 unit is a tap water purifier. My unit cost £180 (approx) and I replace all three pods annually (£70). This particular model purifies 8000 imperial gallons. To merit such an outlay depends on how many aquariums to have to maintain. There is a very much cheaper purifier you could consider, single cartridge, filters 38 litres per hour. You then have to add pH adjuster and Electro-Right. Over here in the UK it costs £40 + £6 for the bottles of adjusters. All you require is a large water container. Also a good memory as it is very easy to forget you have put it on as it takes approximately 1 hour to acquire 10 imperial gallons! If you have say 6 tanks this is an economical unit. I am sure there are similar units available in the USA / Canada and will be a lot cheaper than the prices we pay here. Helen, Scotland. From: Barry, Don <DBarry@demattia.com> > I'm curious to know whether the 'Purity on Tap MM80' is an >affordable tap water purifier or one of the big bucks RO units. Is it >possible to find something worth getting for under $100? ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!