AWC Intervals.

[Cuong]

So I've been piecing together the necessary components to rid myself of buckets. I've already plumbed the output of my RODI unit to the top-off in my Red Sea 650 max to always have fresh water on tap. I purchased a 60 gallon ATO reservoir that I'm going to use to mix New saltwater. From there, I have my new Stenner DMP5-170 hooked up to recycle the new/dirty water to/from the tank..... I'm all set. I'm just not sure what to do with it all.

My question is what are most people's opinion on how much and how frequently water changes should be done? Changing out daily, vs weekly, vs biweekly even??? I'm running a pretty large ato, so 40%+ changes could be done if necessary, but would it be beneficial in the long run to make such large cycles.... My tank is running quite a few SPS so I don't want my parameters to swing too much. Should bi-daily changes of a 4 gallons work better than bi-weekly 20 gallon changes???? Just curious what most people have found most success with.....

 

[billw]

The best way to keep things stable would be to make many small changes. As far as how much, I would think that has to do with your individual circumstance (Size of your tank and water quality ). I run a Litermeter on a 240 gallon tank plus maybe 75 gallon sump. On a moderately loaded system, I change 8 liters a day which works out to around 20% a month. The Litermeter makes 150 changes a day. There wasn't any science behind the 20%/month, just an arbitrary number I set up. It's possibly a bit high if anything, but the tank isn't complaining .

 

[Randy Holmes-Farley Verified Community Expert]

With my AWC system using a dual head Reef Filler pump, I changed about 1% daily, using a bunch of 15 minutes periods each day and night.

IMO, that's a better way than less often, larger changes. It is a bit less efficient, but stresses nothing and you need not match anything in the new salt water to the tank (not temp, salinity, etc.).