I used b-ionic years ago.. then "upgraded" to a calcium reactor. About 5 months ago I switched back to a two part additive (soda ash and calcium chloride).
When I switched, I stopped all alk / calcium / magnesium additives for 7 days. I measured on day 1, 4, and 7 my levels (3 measurements of each parameter each time, and averaged the results.) The results were consistent in that I used the same amount of calcium / alk / magnesium per day.
With two-part solutions, I know the exact concentration of calc / alk. I also know my water volume, and how much I am consuming. Simple math from there tells me how much of each two part solution I need to add every day to replace what my tank consumes. I have it dosed by a peristalic pump. So in my setup, I know for certain exactly how much alk and calcium is being added every day to my system. In the last four months, I only needed to change (increase, as I added a few new corals), my dosing amount. Since I know how much I add per day, I can calculate how much to change the dosing amount by to keep up with demand. When I need to make up more, I know that the amount I am adding will be identical to the last time it was set up. Additionally, changes to the amount dosed are instant. Last, the only thing I need to change is the amount dosed per day.
The potential causes of errors to my method:
1) Incorrectly mixed solution (I measure the additives by weight)
2) Solutions run out (in clear bottles, easy to see if I am running low)
3) Change in alk / calcium demand of system (add / remove corals, growth, lighting change, etc)
Now take the calcium reactor setup... there is no way to know how much alk / calcium you are adding per day. To know if a change to a reactor is the right change takes days to determine. And for me, the biggest problem with a calcium reactor are that too many things can change, so even if you have it dialed in perfect today, 3 days from now it is off again.
The potential causes of errors to a calcium reactor:
1) Bubble count drift (needle valve shifts, CO2 tank is running low (but not out yet))
2) Effluent rate drift (input pressure changed, lines clogged, less backpressure as media dissolves)
3) Internal chamber pH drift (effected by both of the above changes, which changes the amount of media dissolved and hence how much alk / calcium is added)
4) Media amount changes (constantly getting lower, which means the amount being dissolved may or may not change depending on the efficiency of the reactor to consume all the CO2)
5) CO2 runs out (hard to see)
6) Media runs out (easy to see)
7) Setting up again (near impossible to have the same bubble count, effluent rate, media amount, etc as a previous time, so go through the whole setting process each time you clean the reactor, refill the CO2, add more media, etc)
8) Change in alk / calcium demand of system (add / remove corals, growth, lighting change, etc)
I tried a calcium reactor for years... and felt like bashing my head against a wall all the time due to the above fluctuations. Maybe I just wasn't good at dialing in my reactor, but every time I checked my levels, something would be off that I would have to correct for (add something, or turn off the reactor and then add something then turn back on the reactor, etc).
So I sold my calcium reactor setup, bought a good dosing pump, bought enough food grade two part additives to last me around 2 years, and still had money left over. My only regret is not doing this years ago!
For those that are interested, here is an excel calculator I wrote for determing how many minutes per day a dosing pumps needs to be on for:
http://www.mspreef.com/files/additives.xls
When I switched, I stopped all alk / calcium / magnesium additives for 7 days. I measured on day 1, 4, and 7 my levels (3 measurements of each parameter each time, and averaged the results.) The results were consistent in that I used the same amount of calcium / alk / magnesium per day.
With two-part solutions, I know the exact concentration of calc / alk. I also know my water volume, and how much I am consuming. Simple math from there tells me how much of each two part solution I need to add every day to replace what my tank consumes. I have it dosed by a peristalic pump. So in my setup, I know for certain exactly how much alk and calcium is being added every day to my system. In the last four months, I only needed to change (increase, as I added a few new corals), my dosing amount. Since I know how much I add per day, I can calculate how much to change the dosing amount by to keep up with demand. When I need to make up more, I know that the amount I am adding will be identical to the last time it was set up. Additionally, changes to the amount dosed are instant. Last, the only thing I need to change is the amount dosed per day.
The potential causes of errors to my method:
1) Incorrectly mixed solution (I measure the additives by weight)
2) Solutions run out (in clear bottles, easy to see if I am running low)
3) Change in alk / calcium demand of system (add / remove corals, growth, lighting change, etc)
Now take the calcium reactor setup... there is no way to know how much alk / calcium you are adding per day. To know if a change to a reactor is the right change takes days to determine. And for me, the biggest problem with a calcium reactor are that too many things can change, so even if you have it dialed in perfect today, 3 days from now it is off again.
The potential causes of errors to a calcium reactor:
1) Bubble count drift (needle valve shifts, CO2 tank is running low (but not out yet))
2) Effluent rate drift (input pressure changed, lines clogged, less backpressure as media dissolves)
3) Internal chamber pH drift (effected by both of the above changes, which changes the amount of media dissolved and hence how much alk / calcium is added)
4) Media amount changes (constantly getting lower, which means the amount being dissolved may or may not change depending on the efficiency of the reactor to consume all the CO2)
5) CO2 runs out (hard to see)
6) Media runs out (easy to see)
7) Setting up again (near impossible to have the same bubble count, effluent rate, media amount, etc as a previous time, so go through the whole setting process each time you clean the reactor, refill the CO2, add more media, etc)
8) Change in alk / calcium demand of system (add / remove corals, growth, lighting change, etc)
I tried a calcium reactor for years... and felt like bashing my head against a wall all the time due to the above fluctuations. Maybe I just wasn't good at dialing in my reactor, but every time I checked my levels, something would be off that I would have to correct for (add something, or turn off the reactor and then add something then turn back on the reactor, etc).
So I sold my calcium reactor setup, bought a good dosing pump, bought enough food grade two part additives to last me around 2 years, and still had money left over. My only regret is not doing this years ago!
For those that are interested, here is an excel calculator I wrote for determing how many minutes per day a dosing pumps needs to be on for:
http://www.mspreef.com/files/additives.xls