I have noticed that my mitrate levels are not going above 5ppm, without water changes. If they stay at that level do I ever need to do water changes?

My tank is heavy planted. there are so many plants that I can not vacuum the gravel.

Thinking about employing some corys to do the vacuuming for me.

Maybe it's your test kit that's the problem. But if those readings are accurate, and that level's stable...no, you wouldn't need to do water changes. I'm sort of doubting it though.

My heavily planted tank read 0 nitrate last couple of times I checked it. This is with pressurised CO2 as well though. I still do weekly or every second week water changes. There's no substitute for a gravel vac and fresh water

When you do a water change you are removing some of everything in the water , not just nitrate. Your plants will use some of the nitrate

My tank is heavily planted, well filtered, and lightly stocked and I rarely do water changes. I don't test the water either so have no idea what the readings are.

There's a lot more crap in the water than nitrate.

LOL Ira, there's no crap in my water. I get it out of the tap, not the toilet.

There's no substitute for a gravel vac and fresh water

I'm with Luke. I rarely have any nitrate detectable in my heavily planted tanks but the fish are definitely healthier if I do regular water changes. There are all kinds of chemicals that build up in an enclosed environment apart from nitrates.

Oh... maybe that's what Ira was trying to say...

Trace elements get used up... you could dose with something like Seachem's trace elements if you're not intending to do regular water changes.

LOL Ira, there's no crap in my water. I get it out of the tap, not the toilet.

Wow, you've trained your fish to get out of the tank and go to the bathroom elsewhere? Cool, how'd you do that?