calcium consumption rate, experts only please

[reef_guru]

since Ca reactors are actually dKH reactors
being an sps freak i have a question for the experts

since putting on my new lights the Ca is dropping 10 ppm daily
the dKH and Mg are staying constant

the reactor has caribsea arm media
the reactor has a second chamber to lower the CO2 output and raise the Ca, dKH and Mg output
the reactor has an effluent flow rate of 20cc/min for 24 hours a day
the CO2 is on a timer for 16 hrs during the day to match the consumption rate of the tank
right now the effluent output is dKH 33, Ca 580, pH 6.7, Mg 1560

1) would you increase the effluent flow rate, keeping the same CO2 bubble rate to raise the effluents pH to 6.8 -7.0 which lowers the Ca, dKH and Mg output, and also extending the on time for the CO2.

2) would you keep the same effluent flow rate, increasing the CO2 bubble rate to lower the effluents pH to 6.5-6.7 which raises the Ca, dKH and Mg output, and also lowering the on time for the CO2.

[Otty]

I am by no means an expert but I'll tell you what I do in my system:

1. I run CO2 24/7 on a PH controller that will shut the valve off if the effluient gets below 6.45 ph. I have the probe inline right after the reactor but before the second chamber of media I use to bring up CO2.

2. I run 1 to 1.5 bubbles per second and adjust the effluient to maintain the 6.5 ph. This is usually a little stream of water just past a constant drip. I have not measured how much is coming out but I can if you want to know.

This keeps my system about 435ppm but as my corals have been growing I have been forced to start dripping Kalk to raise my Ca to around 500ppm. I usually add about 1 cup of Magnesium Chloride flakes (Hexahydrated) every 10 to 14 days to keep the Mg around 1400ppm. Mg is something I am going to put on a doser after I get the custom Kalk reactor (That Tangster made) up and running good. Hate to do two different things at once because I can't really tell what is changing what.
Don't know if it helps with your question or not!

[Jason McKenzie]

So are you saying that if you leave everything the same as above you will test -10ppm of CA per day. at these current settings?

J

[reef_guru]

since putting on my new lights the Ca is dropping 10 ppm daily
the dKH and Mg are staying constant

jason, yup thats what im saying

Ca is dropping by 10 ppm within a 24 hr period on the current reactor effluent output and has been since the new lights, so if i test the tanks Ca today @ 480 in two days it will be @ 460, and so on, without doing anything to the tank.

prior to the new lights there was nothing to do, all levels stayed constant. the lights have been on for a week and a water change has not been done since ( in case you were wondering since most salts dont match the tanks parameters ). the only element that is dropping is Ca.

otty, the way your system is set up works also.

my system is set up for the CO2 to be turned on with a timer during the day to match the consumption rate of the tank. that way there is less of a pH drop at night in the tank. my system is also automatically dosed with all liquid seachem reef products at a rate of 40cc a week with trace, plus, dKH and complete.

in order to keep up with the calcium demands for right now, im also dosing calcium liquid seachem reef calcium until i figure out what to do with the effluent of the reactor. i also have dry seachem products, calcium hydroxide, kalwasser and calcium chloride that i can dose but would rather use liquid seachem reef calcium at this time.

[Otty]

The only reason I can come up with is your new lights have spawn new accelerated growth in your corals....a good thing. I am trying to make my tank as low maintenance as possible so that is why I am working on reactors to do all my dosing.
I seen your review on the dosers. Are you useing them now??

[reef_guru]

yea, the consumption and growth rates have gone up due to the lights and hopefully continues. low maintenance is possible which is also why the reactor has always been used. the liquid seachem products are dosed for the added umph and the reviewed products that i entered are from my system. all of which work great.

with regards to the reactor, its not the Ca that should be watched its the dKH. so with that which one of the first two mentioned options, both of which could produce the same effect, would yeild a greater return. since the added supp was introduced that may have sovled the problem for now. imop #1 would be the best option but was wondering what the experts think.

1) would you increase the effluent flow rate, keeping the same CO2 bubble rate to raise the effluents pH to 6.8 -7.0 which lowers the Ca, dKH and Mg output, and also extending the on time for the CO2.

2) would you keep the same effluent flow rate, increasing the CO2 bubble rate to lower the effluents pH to 6.5-6.7 which raises the Ca, dKH and Mg output, and also lowering the on time for the CO2.

[Otty]

I was always under the impression that the effluient should be 6.4 to 6.5 ph in the reactor for the best calicum transition. If you speed the effluient up then it will have less Ca because of the dwell time in the reactor. More time in the reactor (slower flow) means more calicum. But there is a point that it will have more Ca in the efflueint but it is not enough for the consumption on the tank.
I believe this is why it takes so long to dial one of these in.
Just my $.02

[reef_guru]

otty, agreed

anything below 7.0 is good enough for todays media to dissolve. media turns to mush if pushed to low and will clog the output line. a pH of 7.0 wont dissolve as much and as a pH of 6.5, there is a happy medium in there somewhere. both Ca and dKH are effected in the raising or lowering of Ph within the reactor and should dissolve at a balanced state.

correct me if im wrong,
for a single chamber: effluent of dKH 20+ and a pH of 6.5-6.8, 6.7 being ideal
for a recirculating chamber with a standard second chamber: the reading should be taken off of the first chamber, if its taken off of the second chamber, then the pH would be higher.
for a standard dual chamber: the reading can be taken off of the second chamber. which i believe is the way yours is set up.

which produces more Ca and dKH within a 24 hour period:
CO2 for 20 hours a day @ 6.9 pH
CO2 for 16 hours a day @ 6.7 pH
CO2 for 12 hours a day @ 6.5 pH

your confusing me here

But there is a point that it will have more Ca in the efflueint but it is not enough for the consumption on the tank.

are you talking about dKH or Ca in regards to the consumption rate, Ca reactors are actually dKH reactors

[Otty]

I put my probe between the first and second chamber.
I wish I had the scientific way to explain this but I am a robot programmer by trade.

If you are slowly dripping the effluient through to pick up the most Ca or dHK, that amount coming out may not be enough to supply a large SPS dominent tank. You would be better off to have the same amount of Ca in a faster stream but that will take more CO2 to produce.

[reef_guru]

your suggesting:

to increase the effluent flow from 20cc/min to 25-35cc/min, raising the CO2 bubble rate to keep 6.7 pH which will raise the amount of Ca @ 580 and dKH @ 33

i thought about that also, but that would raise the dKH in the tank.