Originally Posted by scottb
I think so. So when my tank is fully cycled, can I ignore the readings from my tap, and simply go with what my tank reads?
I'm sorry I'm being so confusing!
Yes, ammonia or nitrIte in tap water won't matter because your bacteria colony will grow to accommodate it.
NitrAte will matter a bit. Because you are removing nitrate but also putting some back in with the new tap water. That's something to be aware of. Nothing to worry about you will just need larger more frequent water changes to keep it low.
Eg: the tank reads 40ppm. You do a 50% water change removing 20ppm BUT because your tap contains 10ppm you are adding 10ppm back in. Your tank will read 30ppm.