If I keep nitrates at 0, how often do I need to do water changes?

[12 Volt Man]

^
strange. I have a 50g tank that is 2 inches off the floor and I can drain it no problem with a python...

however, if you have lower water pressure you will not achieve as good suction. perhaps that was your issue.

 

[fox3]

I have a 40G breeder as a sump/ fuge onna 210G Display tank. I've used Hornwort and it works great but fouls the pump well. I've got it loaded with wysteria now and it keeps our overstocked tank at 10 ppm nitrAtes using very low lighting.

If I up the lighting in the fuge the trAtes go down under 5 ppm but the BlueGreenAlgae starts to grow and I need to fertilize and turn off the tank lights to rid it. I have found with my feeding habits that 10ppm is as low as I can go with out the algae taking over.

 

[Oreo]

You can go a good long time without water changes. I used to let my nitrates get up into the hundreds of PPM. All the livestock in the aquarium seemed plenty happy and none the wiser.

Figure on doing 75% water changes once a month, or once every other month if your filter is good and your not stupidly overstocked.

Plants aren't likely to solve any problems for you. Ask me how I know. Go ahead.

 

[m1ste2tea]

I have exactly what you are trying to do, a bottom, planted tank. I do have to say siphoning is a pain, and the plants sometimes need more work than the water changes themselves.

If you want to go this route, Id start with a heavily planted tank, maybe one or two small fish to see how they balance out with your nitrate levels.

If your plants are sucking up all of the nitrate, then 2 weeks without a water change is perfectly fine.

I personally believe that if your fish do not tear up the plants, you should always strive for a planted tank. but like others have said, theres plenty of benefits from doing regular water changes.