Change Water with 0 Nitrates?

[robby]

I have a planted tank set up with a few ottos and platys and snails. My ammonia, nitrites and nitrates are always 0 across the board, and have been for months. I do a monthly water change out of habit, but I'm wondering if there's any point. Is it helping the fish? Is there any point in changing the water if there is no readings of toxins?

 

[Critterlvrok]

I would say yes. You at the very least want to be replacing minerals that the fish and plants use. However, I am not an expert. Just my opinion.

 

[Rokuzachi]

I've read that fish excrete compounds (hormones and the like) which cannot be used as nutrients by plants and that it's another reason to still do your scheduled water change in addition to the reason Critter listed. I can't vouch for the validity of that info though.