kalkwasser reactor and vinegar?

[alan.timms]

Hi,
I've been using a calcium reactor for a while. Water flows through the reactor all the time, but the C02 is on a timer so it only runs at night, as I'm having trouble keeping the pH up. I also add 2 litres of kakwasser to the tank, dripped in at night: after reading a chemistry explanation I don't really understand, I dissolve the kalkwasser powder in clear vinegar before adding it to RO water, allowing it to settle, and syphoning off the saturated solution to drip into the tank. Apparently this releases more calcium, and reduces precipitation.
I'm trying to automate the system, and thought about fitting a kalkwasser reactor with a dosing pump that would drip 2 litres of solution in at night without my intervention: I'm looking at the AquaMedic system.
My question is, should I treat the kalkwasser powder with vinegar before adding it to the reactor? The theory is that I can then recharge the reactor every 2 - 3 weeks, rather than mixing / syphoning / dripping in a dose every day . . . any helpful comments would be gratefully received.

 

[Anonymous]

Why you not run your calcium reactor 24/7? Concern about low pH? I would try to work with whatever you have already if you can't keep up with the calcium demand, instead of doing additional things. Is there anything wrong with your tank that you are not happy with for you to look at additional methods?

 

[alan.timms]

Hi,
Thanks for the response.
I don't run the calcium reactor 24/7 because I'm struggling to get the pH up - it hovers between 8.0 and 8.1. The calcium level is 400 - 420 so that isn't the problem.
I'm already adding 2 litres of saturated kalkwasser solution a day " by hand" so the machine would just automate the system: I'm not changing quantities, just trying to make the job easier.
The question I was asking is about adding vinegar. I currently dissolve 5cc of kalkwasser powder in 5cc of white vinegar before mixing it with RO water to settle out - according to an article on this site http://www.reefscapes.net/articles/bree ... asser.html this makes more of the calcium available to the corals, and reduces the calcium that reacts with carbon dioxide to form useless chalk. The article says that any leftover vinegar forms food for the anaerobic bacteria that convert nitrate into nitrogen gas, which evaporates: win, win! But should I put straight Kalkwasser powder into the reactor, or treat it with vinegar like I currently do? AquaMedic say it won't hurt the reactor, but they don't know what it will do to the corals . . . .
I'm not sure about the chemistry: using vinegar could be fine, or it could be that "straight" kalkwasser continues to react over time, but vinegar treated kalkwasser releases all in one big hit, which isn't a problem if it is made fresh every day, but wouldn't release in a steady stream for 2 - 3 weeks in the reactor, like untreated kalkwasser powder does. Any helpful chemists out there, please?

 

[Anonymous]

Hi Alan, Randy Holmes Farley has demonstrated that the amount of calcium that reacts with CO2 is actually quite low in volumes of kalkwasser where there is a surplus of calcium hydroxide powder:
http://reefkeeping.com/issues/2003-05/r ... /index.php

For this reason I tend to avoid kalkwasser reactors simply due to cost and complexity. I make up a large volume of kalkwasser with vinegar that lasts about 2 weeks all at once, and then drip it in with a peristaltic pump. It doesn't require a sealed vessel or a mixing bar or any of that stuff, just a 5 gallon bucket with a lid and a peristaltic pump.

I do the same as you and dissolve the powder in the vinegar, and then add to DI water. I use about 150mL of vinegar for every 50mL of calcium hydroxide powder, but only after slowly increasing the amount of vinegar after several weeks. It's also pretty important to have a good skimmer if you intend on adding vinegar to your kalkwasser as the increased bacterial growth can lower dissolved oxygen concentration.

Hope this helps.

 

[alan.timms]

Hi Matt,

Oh b****er! I got impatient and ordered a kalkwasser reactor!
Not understanding the chemistry, but knowing the liquid syphoned off the kalkwasser / vinegar mix reacts with C02 I dismissed the idea of making up a large volume. I planned a container: I got as far as thinking I could line a 20 kilo salt bucket with the plastic bag the salt comes in, then seal the top of the bag round the outlet pipe with a cable tie, excluding all the air. As the water is pumped out the bag collapses, keeping the mixture C02 free . . . . . any good as a modification to your system?
My skimmer lifts an inch of brown liquid into it's six inch container per week, so I should be OK with the extra waste.
My main concern was to know if mixing the vinegar into the kalkwasser powder released everything in one go, and hence wasn't suitable for using in a reactor I recharge every 2-3 weeks, and you have answered that for me, thank you.
I'm not just lazy: I have M.E. ( I think you guys call it chronic fatigue syndrome?) so everything has to be as easy as possible, not involve heavy lifting, and not need to be done at a specific time, in case I get several bad days in a row.
My RO filter works off a pump controlled by float switches and a pressure switch, so I just switch it on and walk away: when the RO tank is full, the back pressure in the pump line switches it off. Float switches top up aquarium evaporation from the RO tank. Once a week I pump 10% of the water from the sump into a drain, then another pump on a float switch refills it from the salt mix resevoir. With my calcium reactor and kalkwasser reactor (when it arrives) I should be about as automated as possible?