Longest you’ve ever gone without a water change

[Danroo]

1 year on my 20 gallon and my hard corals went on a stasis period, no growth no coloration with the longest time of keeping nutrients at 0. Got Dino’s after trying to raise my nutrients. Softies exploded in growth with is good I guess.

 

[d2mini]

Water changes do two things:
1. Control nutrients
2. Replace vital (and not so vital) elements

If you can do these two things well, you don't need water changes.

On my previous tanks I did many small water changes throughout the day automatically and ran a calcium reactor to provide major and some minor elements.

On my current tank I'm following the Reef Moonshiner's program with no (or very minimal) water changes. I'm only a year in though.