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icebrg5
04/06/2015, 06:37 PM
Does it matter what temp the RO/DI water is at when mixing kalk into it?

Wondering if warmer water helps the kalk dissolve better.

Can the undissolved kalk that settles at the bottom be mixed when the next batch is made or should it be dumped out?

Nanighan
04/06/2015, 07:39 PM
I read somewhere (awhile back) that cooler water dissolves it better. Look up kalk slurry and the guy recommends coldl water.

joshbrookkate
04/06/2015, 07:46 PM
Good question about the sediment at the bottom. I'm following to find out.

RocketEngineer
04/06/2015, 08:11 PM
Does it matter what temp the RO/DI water is at when mixing kalk into it?

Combining water and kalk creates heat. Add a small amount of water to a large amount of kalk and you can actually get the water to boil. That is why you should always add the powder to the water, gives it time for this reaction to occur and allows the heat to dissipate through the water.

Wondering if warmer water helps the kalk dissolve better.

Not enough to be noticeable and once it comes back to room temperature in the container, the dissolved amount is the same for either starting point.

Can the undissolved kalk that settles at the bottom be mixed when the next batch is made or should it be dumped out?

Kalk reactors work by having a larger volume of powder than can dissolve into the water present in the reactor so that when new water is added, some of the undissolved portion dissolves into the water, maintaining the concentration of the lime water that exits the reactor.

What you want to avoid is having a pump in an ATO container push this slury into the tank. Because it is very basic and is heavier than water, if it gets into the system it can land on things and cause chemical burns. Folks who dose kalk from a resevoir make sure the inlet of the ATO pump stays off the bottom of the container so the slurry/sludge can settle out and only the clear lime water is dosed to the tank.

A good read on this topic: What Your Grandmother Never Told You About Lime (http://www.reefkeeping.com/issues/2005-01/rhf/).

HTH,

deleau
04/06/2015, 09:20 PM
A good read on this topic: What Your Grandmother Never Told You About Lime (http://www.reefkeeping.com/issues/2005-01/rhf/).

That article is a must read, IMO, for anyone doing kalk.

I rotate top off containers and pour what's left from my "empty" container into the new one (my ato pump doesn't pump it dry...on purpose).

Ever 5 or 6 times, I will pour out the slurry instead of pouring it in the next container (based on the precipitate section of that article). I probably don't have to do that, but pickling lime is so cheap, it's not a big deal.

PhaneSoul
04/06/2015, 09:46 PM
Also the slurry at the bottom may contain phosphate if there happens to be any phos in your ro/di water. a plus is to run your drip line for the kalk to the inlet of your skimmer so that any phos bound with the kalk has an immediate turn to go thru ur skimmer to be removed

icebrg5
04/07/2015, 04:09 AM
Thank you all for the help.