How often do you do water changes?

[z28pwr]

I do a water change whenever it seems necessary. I've gone 6 months without a water change with no problems, but I do have 350 lbs of LiveRock and 11 fish in a 380 gallon aquarium.

[NaCLreefer]

how does topping off evaporated water affect the tank? are we still adding trace nutrients when we are adding ro/di water?

[bigdscobra]

Topping off evaporated water keeps the salinity constant, ro/di has no nutrients in it thats why the salt has so much if you have a good Ro/di unit your water will only have ~.001% of trace elements left in it, at least thats what my 6 stage unit claims.

All I know is from experience and my system is ~105g or soo and doing a 10g water change every week has made a difference. My softies are bigger than ever, my open brain is huge and I have noticed greater polyp extention in SPS. I have no fancy equipment just a 20g fuge, seaclone 100, and some filters to add carbon.

I use to do the water changes when ever maybe twice a month, but the last 2 months I have been doing them every week and thats why I notice the difference.

I plan on doing the same this summer when I get the 180g reef setup but with sump, fuge and prop tank ~400g system, I am looking at 40g every week water change.

[NaCLreefer]

thanks for the answer!