For those who run kalkreactors and calcium reactors..
 

Few years ago when I had a reasonably successful SPS reef, I ran both a kalk and a calcium reactor on my tank and thought I had pretty decent results.

Thought I'd go back to trying both now, but am noticing a couple things.

For the most part it looks like I'm unbalancing my Alk from my Ca. With the slowest of steady drip rates (about 1 drop per second) on the kalk reactor, I'm getting Alk around 4.0 meq/l (about 11.2 dKH) and Ca is about 370.

I'd kind of like to see my Alk back off a bit or my Ca bumped up a bit, but increasing either reactor spikes my Alk to well above 4.0meq/l, which is way too high.

For those running both, what kind of levels of Ca and Alk are you getting?

Whoo, late night eh Tony?!

I don't have any personal experience running both reactors, but couldn't you just bump the Ca levels up with an additive and then attempt to maintain it with the reactor(s)?

I would think adding more kalk would increase the calcium and not increase the alkalinity, which is being kept up by the co2 reactor.

I don't have a kalk reactor but i do drip kalk at night. My calcium sits around 390-400 and my alk is at 9.5-10 DKH

I'm of the same opinion. While my current tank runs both, I haven't had it running long enough to spot a trend. My LONG term experience is running Kalk only..which always tended toward low Alk.

So..IMO, the running of your Kalk reactor should only improve your current situation.

I run both, my kalk reactor is run on my ATO though. Alk 3.0 meq/l and Ca 400 ppm.

Hi Drew, yeah I was working on my tank build last night. I only get to work on it after the wee one goes to bed. There's only 1 of him but it feels like I'm chasing after 6 or 7 toddlers. :lol: So there's no progress on anything while he's up.

Well, that's weird then. I thought the kalk was to help with the Alk and not the Ca. Guess I had that backwards but I've really been struggling from keeping the Alk from going through the roof ever since putting both online.

I should mention that I do add Calcium additive to bump the Ca levels but it creeps downward over the course of a week. Which means despite the abundance of Alk output, the reactors are not keeping up the Ca levels.

I should mention that I'm running the reactor at pH 6.7 and an effluent flowrate of 60ml/min. Unless my pH meter is in dire need of a calibration but given that it tells me a pH range of my tank from 8.1 (night) to 8.3 (day), I've not had cause to think it was out of range since the numbers are more or less what you'd expect to them to be.

I wonder if the thing to do here is take them both offline for a week or so and let the levels drop, and just keep bumping the Calcium via additives until the Alk has gotten to maybe 3.0, and then restart. It's just that... well .. I've already kind of tried this once already when my alk approached 5.0 meq/l :eek: ...

Just running a Ca reactor only but finding similiar.

I can keep the Ca around 400ppm with the reactor alone but find my alk is always on the high end (11dKH) and if my effulant rate drifts up (bubble count same) then the alk wants to spike.

Been testing my mix water lately and find IO is at 11 right out of the bucket, have been considering bringing the alk down before adding to tank to give me some more head room with the tank. That and a finer valve for the reactor effulant.

Well, kalk will add both Ca and Alk, as will a Ca reactor. Tony, on my 150g, once I set the parameters where I wanted them using Kent A&B, my Ca reactor was able to maintain those levels all the time. I never needed both, and that was with a lot of SPS growth. If your Ca reactor is sized to your tank/bio-load, maybe just try running that AFTER you set the right levels.

Just to expand on the topic....Anyone using a kalk reactor mainly to help bring up the ph drop from their calcium reactor? I was under the impression that this is the main reason to run both.