Automatic Water Changes And Balanced 2 Part

[LadyTang2]

I read a great article by Randy called "Water Changes in Reef Aquaria" but it left me with a question. A 1% daily continuous wc is nearly sufficient to maintain mag levels, but is not nearly sufficient to maintain ca and alk.

So with 1% wc per day and dosing a balanced 2 part like b ionic or 3 part balling, wouldn't mag rise too high? And this would also be true for any trace that was being held nearly constant by wc? Any idea on which traces behave like mag and would be driven to high w balanced 2 part?

Did I get this right? If this is true then can you not use b ionic? It seems like you need to take a lot more into account when dosing if you're doing cont wcs since the cont wc is replenishing certain things more than others relatively speaking.

Edit* Continuous would have been a better word to start the title with rather than automatic

 

[FishTruck]

In my experience, I do not need to supplement Mg when doing lots of water changes, which would work out to 60-120 gallons per month in my 400 gallon-ish system (roughly similar to 1% per day). But, I still need to run a calcium reactor.

In your case... I think you would just need to break up your Alk / Ca and Mg dosing into two groups (balanced Alk and Ca and variable Mg) and watch your levels, right? So, you would avoid a mix that contained all three parts of your dosing in less than three containers.

I think since consumption of Mg and trace is low... by removing water and replacing with new - you will keep these levels sufficiently high with no risk of overdosing - since your additive is at the correct saltwater concentration.

Think of your water change as a correction... not a supplementation. It will correct up or down and always take your tank water closer to new sea water.

The other thing to watch is rising salinity - which I think can be an issue with balling.

 

[infinite0180]

Your forgetting an important concept. The gradual rise in salinity from dosing a balanced 2 part, which you will be correcting for, either by replacing salt water with fresh water every so often, or like in my case, my skimmer keeps up with it. By maintaining the 35ppt salinity youl keep everything in check...

 

[Randy Holmes-Farley Verified Community Expert]

I read a great article by Randy called "Water Changes in Reef Aquaria" but it left me with a question. A 1% daily continuous wc is nearly sufficient to maintain mag levels, but is not nearly sufficient to maintain ca and alk.

So with 1% wc per day and dosing a balanced 2 part like b ionic or 3 part balling, wouldn't mag rise too high? And this would also be true for any trace that was being held nearly constant by wc? Any idea on which traces behave like mag and would be driven to high w balanced 2 part?

Did I get this right? If this is true then can you not use b ionic? It seems like you need to take a lot more into account when dosing if you're doing cont wcs since the cont wc is replenishing certain things more than others relatively speaking.

Edit* Continuous would have been a better word to start the title with rather than automatic

No, water changes do not impact how to use a balanced calcium and alk supplement two part. No rise in mag (or depletion) is expected.

 

[Randy Holmes-Farley Verified Community Expert]

Your forgetting an important concept. The gradual rise in salinity from dosing a balanced 2 part, which you will be correcting for, either by replacing salt water with fresh water every so often, or like in my case, my skimmer keeps up with it. By maintaining the 35ppt salinity youl keep everything in check...

Right!

 

[Randy Holmes-Farley Verified Community Expert]

In my experience, I do not need to supplement Mg when doing lots of water changes, which would work out to 60-120 gallons per month in my 400 gallon-ish system (roughly similar to 1% per day). But, I still need to run a calcium reactor.

In your case... I think you would just need to break up your Alk / Ca and Mg dosing into two groups (balanced Alk and Ca and variable Mg) and watch your levels, right? So, you would avoid a mix that contained all three parts of your dosing in less than three containers.

I think since consumption of Mg and trace is low... by removing water and replacing with new - you will keep these levels sufficiently high with no risk of overdosing - since your additive is at the correct saltwater concentration.

Think of your water change as a correction... not a supplementation. It will correct up or down and always take your tank water closer to new sea water.

The other thing to watch is rising salinity - which I think can be an issue with balling.

Using a two/three part as directed also does not risk overdose. They are designed with the expectation that magnesium demand is low. They also do more than magnesium (i.e., sulfate relative to chloride), and I recommend using the third part regardless of the magnesium level (unless it is actually too high for soem reason).