Will a water change suffice??

[vontill]

stop using tap water to top off. I checked the nitrate level in my tap water and it was between 50 and 100. in the beginning we didn't know any better and we couldn't figure out why water changes weren't helping. I tested my tap and it was all crazy which is why my children don't drink it.

 

[socal57che]

Recent studies show that tap water in many municipalities contains pharmaceuticals that have been flushed down the toilet. Combine that with all the other dissolved solids, and it's easy to see where it could cause problems when used for base water in a marine aquarium. A couple years ago our water company mistakenly introduced 3 times the regular amount of chlorine. It was so bad hat it burned our eyes to shower.
I'd definitely switch to RO/RODI water.
And ask your city for a water test statement. Most are required to make their test results available upon request.