Calcium reactor - CA vs Alkaline level?

[bananags]

hi,

i finally got my calcium reactor up running: 7lbs korallin + a small amount of Mg rock

Build using this plan: http://www.melevsreef.com/dj88.html

I read a bunch of stuff on how to tune and start a new calcium reactor set up, but there are a few things that I am not clear and need some pointers.

Initial level before reactor run: (using salifer test kit)

~360 Ca

~10.2 dkH

8.0 pH (tank)

-Effluent set for steady Drops to a cup

-Ph controller is set measure effluent pH level set ==> ~6.6 (cut off Co2) (Milwaukee brand Co2 controller/just calibrated)

-Bubble count set at ~120/min

From what I read, bubble count does not really matter if I have a Co2 controller, as long as I can get to the proper pH 6.5-6.9 level (effluent side at output ie second chamber) with my bubble count setting to melt Ca material, any adjustment to effluent flow rate will need to compensate with Co2

(i understand the concept, enough Co2 in the reactor to drop pH, let the controller take care of the rest)

After 3 days run of the reactor: (steady, measure once in each 24hrs interval)

~420Ca

~14.5dKH

8.0pH (tank)

===> is the 14.5dKH level normal? if not how do I fix this?

I think my goal was around 440 Ca, somewhere between 7-11dKH

IF I understand this correctly, you can't increase Ca level w/o increase alkalinity

Thus, if my system right now is at 420Ca and 14.5dKH ==> how do I fix this?

or how to I get to Alkalinity back down to in the "good" range 7-11.5 w/o effecting my calcium level

Thanks

Anh

Edited September 2, 2008 by bananags

[+ACampbell]

A water change with salt that contains low alk levels, such as tropic marine pro, will help to level things out.

[GKarshens]

Sounds to me like you have the effluent running out too quickly. A calcium reactor should not raise Ca levels but maintain them. I would slow down the drip coming out of the reactor.

[Headless_donkey]

Just throwing it out as an alternative. Some people(including me) have had success running their CARx on a timer(only run it at two hour intervals or some variation). I have also heard of people opening their effluent up all they way. The theory would be decreasing the water's dwell time in the reactor would lower the ALK/CA dissolved. I have not tried this.

[bananags]

thanks for the response everyone.

I am due for a water change, so I'll make up a bit more water than normal and try the water change

Already tune down the effluent rate

CA reactor on timer eh, i may look into that, save from $$ on electricity hee hee

[bananags]

Just a quick update after a lot more read-- maybe it will help others in future

-Corals consume alkalinity and Calcium at a fix ratio, ie Alk and CA are directly tided, can't change one w/o effecting the other, and there is no chemical for reef than can reduce these levels, just let nature take it course.

-Magnesium has something to do with how well the coral absorb Alk/CA , need to keep Mg at some reasonable level

(forgot already, but oh well, just need to know mg is needed, I have some mg rock in the reactor for this)

Before start CA reactor, make sure Alk/Ca level of your tank is at the proper level 10kdH and 420ppm or what ever you decided. My first mistake, I did not realized this: can't increase Ca w/o increase Alk, and dropping one will drop the other

CA and Alk level, don't really need to worry about Mg yet.

--> if levels are low: fix by adding buffer for Alk, or Ca (ie Kent turbo calcium or similar) ==> don't use limeswater for this ==> you want to add Alk and Ca separately to adjust them individually to the proper params

--> if levels are high (either one) --Unlikely, but it could happen (my case): water change or do nothing, just wait, your coral will consume it and drop it down to the proper level

(there is no quick fix or chemical fix if the level is high, beside water change, but why waste the good thing)

To fix my level, I used: magnesium salt, kent alk buffer, kent turbo CA, I wait for my Alk to fall back down within range while just add Kent Turbo Ca raise the CA only while Alk is dropping (consumed). measure 10dKH and 380 ca measured this AM, took about 3 days to get here.

Also, running CA-RX on the a timer (YEAH baby, great suggestion) ==> now the ON duration of the timer is the amount of the CA/Alk feed to the tank, pH controller will take care of the rest.

Thanks again for reading. now, I will wait and see how well the tank do with a Ca- reactor instead of dosing..So far, the coral has showed a lot of grown all direction since last week as I have been monitor the level more carefully.

Anh

Edited September 11, 2008 by bananags