I have HORRIBLE water here in AZ. I bought a 5 stage RO system on ebay by a company called Aqua-safe systems. I researched all the vendors and he was the best, had excellent feedback. They system includes everything for $130. I didn't install it under my kitchen sink, I just hook it up to the hose bib outside when I need water. (you just need to request the hose bib attachment.) Even replacement filters are cheap. If you are really going to be in this long term, I would suggest investing in one and trying it out. My system even came with a TDS meter, which tells you in a reading (0-1000) how bad your water is. The higher the number, the worse it is. My tap water was about 640 TDS, and the RO system got it down to zero TDS. Your tap water will GREATLY affect the algae and health of your tank. Also, if you initally fill your tank with tap water, it will take MANY many water changes before that water is diluted and gone. Good luck!