How often to add new kalk

[dolph]

I have a GEO kalk reactor that I use to dose Kalkwasser into my aquarium. It is attached to my top-off system. Nearly two gallons of water evaporates from my tank daily and is replenished with fresh ro/di water which is run through the reactor. My question is this. How do I know when to add new kalk media to the reactor and how often should this be done? The directions say to add 1/2 cup of media (kalk) but it doesn't say how often or how to determine if or when new media is needed. thanks for any help.

[Randy Holmes-Farley]

You can monitor the potency of the effluent (best by conductivity, 10.3 mS/cm or so is saturated), but it also possible to crudely measure it by pH,) or you can monitor alkalinity in the tank. Assuming it has been steady previously, then it will drop as the limewater looses potency.

[chase33]

Thank you for the response. I think it's easier for me to monitor the alk but how do you monitor by ph? Is it supposed to be a certain level in the reactor and if so what is the level? I've can't find any articles related to this specific area/question. Thanks again.

[Randy Holmes-Farley]

You can measure the effluent pH directly with a meter. The pH of saturated limewater is 12.5 or so, but your meter may be be accurate at that pH. Measure for sure saturated limewater as a standard (say, 2 teaspoons in a cup of RO/DI). Measure that and note it. Then if the pH of the effluent is 0.3 pH units lower, it is about half saturated. 0.6 pH units lower is 1/4 saturated. 0.1 pH unit lower is 80% saturated, etc.

I discuss limewater in detail here, but do not provide reactor directions since they are somewhat specific to different reactors:

What Your Grandmother Never Told You About Lime
http://reefkeeping.com/issues/2005-01/rhf/index.htm

[chase33]

I got it. thanks.

[dolph]

Thank you

[Randy Holmes-Farley]

:thumbsup:

Happy Reefing. :)