Right now I've got 2 10 gallon tanks and 1 30 gallon tank. One of the 10 gallons only has a small pleco and a female betta in it. The 30 gallon has a couple goldfish. The other 10 gallon is empty (been trying to figure out water problem described below before putting anything in it) Spent months struggling with the tanks on our crappy (hard) tap water that uses chloramine and has a ph of over 8, so I could never get the ammonia to safe levels. Decided to buy an RO unit. Didn't seem to help ammonia "problem"? Run the full gamut of tests against the water straight out of the RO unit, measures 0 in everything and ph of 7 (even with the API tests). Put all brand new (washed) rocks/decorations in the second 10 gallon, all new filter/media, etc and filled up the tank (no fish added). Tested that tank the next day, ammonia over 8ppm via the same API kit that said 0 before and nothing else added that should give false positive like Prime or any declorinators, but did add Replenish. Nitrite/Nitrate is still 0ppm. Next step was to put in Prime (know that can cause false positive) and beneficial bacteria, wait a couple days and test again. No change, still 8ppm+ (Nitrate/Nitrite still 0) Bought a Seachem ammonia tester (that tests both kinds of ammonia) results said 0 ammonia. Bought a little Seachem "hang it in the tank" ammonia tester... 0 ammonia. Other 2 tanks, identical results, so this is getting very frustrating. Tried doing multiple days of 50-75% RO/Replenish water changes in the tanks, reading of 8+ppm ammonia doesn't change. (Nitrate/Nitrite still 0 in all tanks) Using the API kit, every time I test the RO water, 0ppm. Every time I test a tank (fish, no fish, water change, brand new tank, etc) 8+ppm ammonia. (Nitrate/Nitrite still 0 in all cases) Does anyone have any idea what might be going on? Are the API tests really that messed up? Or can something else be giving false ammonia readings with the API kit that we're not considering? The fish all seem to be acting normal and not showing issues with the water, but I'm worried there is something going on that we're overlooking so looking for some advice.