I assume you have very hard water where you live?(RO water being soft)Just thought I'd update, returned to a different LFS for another test (using API) and it turns out our ammonia and nitrite are spot on just nitrate is a bit of a prob. So, after purchasing our own liquid test kit (for cheaper than the internet) it turns out nitrate levels in our tap water is relatively high to start with. We have completed a 25% water change with RO and shall test again tomorrow. Fingers crossed!
What was your tap water nitrate results?
can you also post us your tap water pH results
Keith.