How often do you change your water?

[04charedcompg]

this topic came up at work today between a few reefers, and i change 10% weekly and they all do 10% bi weekly, my filtration setup is superior to theirs, they dont even run skimmers. Im just curious if im over doing it or are they under doing it? thanks everyone!

[MizTanks]

I don't understand the NOT good for nutrient export comment but oh well :)
I change out 6g 1x weekly. I am running a nano skimmer also. I dose 2part daily.
I think it all really depends on your other filtration. Skimmers, reactors and the like.

[dputt88]

15-20% bi weekly. i dont miss waterchanges.

[Tom@HaslettMI]

I perform 10% changes once a week (occasionally missing a week here or there).

Whether a tank needs weekly or biweekly changes has a lot to do with nutrient inputs and trace element removal.

I have also heard that nutrient removal via small % water changes is not terribly effective. I'll post some info on it... if I can find it.

Tom

[Saltwaternoob]

I perform 10% changes once a week (occasionally missing a week here or there).

Whether a tank needs weekly or biweekly changes has a lot to do with nutrient inputs and trace element removal.

I have also heard that nutrient removal via small % water changes is not terribly effective. I'll post some info on it... if I can find it.

Tom

I do 10% weekly.

Think of it this way say you have a 100g tank with 100ppm of nitrates. If you do a 10g water change nitrates will only drop to 90, and the next week 81, next week 73 and week 4 67ppm(assuming you dont produce more probably more like 80ppm). But if you do a 40g water change at once it would be 60ppm.

[Tom@HaslettMI]

I do 10% weekly.

Think of it this way say you have a 100g tank with 100ppm of nitrates. If you do a 10g water change nitrates will only drop to 90, and the next week 81, next week 73 and week 4 67ppm(assuming you dont produce more probably more like 80ppm). But if you do a 40g water change at once it would be 60ppm.

Thanks for supplying the rational!

Tom

[MizTanks]

I guess I'm still a little confused as to how removing water wouldn't be removing nutrients? Are all the nutrients just sitting on the rock and sand? What does a skimmer remove from the water?

[Saltwaternoob]

I guess I'm still a little confused as to how removing water wouldn't be removing nutrients? Are all the nutrients just sitting on the rock and sand? What does a skimmer remove from the water?

Water changes are the good for nutrient export, I dont know if the above poster ment using it as a sole form for controlling water chemistry. Or that small volume water changes are not effective at removing large quantities of organics.

Nutrients get broken down by the bacteria in the rock/sand Ammonia- nitrite - nitrate in that order.

Skimmers remove organic materials hopefully before they break down in to waste.

[bigbill]

i change 30 gallons a week in my reef tank 100 Gallons total vol so 30 % my fish only i do 10 % monthly
i have a lot of sps and mixed corals in it but i over feed so i do more then normal imo