kalk melting ???

[conrad]

Instead of pouring, dripping, or dosing kalk, do you suppose one could make kalk ice blobs and float them in the tank to dissolve slowly and help lower the temperature a bit? I don't know what temperature kalk would freeze at, or if there would be any chemical reaction issues. I may try an experiment, but figured I'd ask first, as it seems obvious enough that someone must have thought of this before.

The ductwork and mechanical systems for our apartment building are such that they can have either the heat or the AC on, building-wide. Apparently in that situation the dates when they switch over are dictated by state law, and I don't think we get AC until June 15th, so I've been nervously watching my temps. I get morning sun on both exterior walls of my bedroom. These walls are mostly window, about 150 sq. ft. of glass. I keep the blinds drawn of course, but still a lot of heat gets in. Fortunately I'm way up above everything else and get good breeze if there's any, but I get really nervous until late afternoon.

My tanks are at a bit over 82 now, but the inside temperature is starting to drop. But I was thinking that maybe kalk ice blobs could help tomorrow morning. Or am I completely daft?

Thanks for any thoughts on this!

--cn

 

[gordonzoo]

This stuff hardenes like cement when mixed and alowed to dry. I always thought about making tablets out of it and dose like chlorine tabs. I would be afraid of it flaking though.

 

[conrad]

Yay, the sun is no longer beating on my room, a nice breeze came up, and the temps in my tanks are dropping. They didn't quite make it to 83F. Not that I have anything super temperature sensitive in them, but still, I worry. But time to sit on the deck with a beer and a book and *enjoy* the sun and warmth.

I may actually try making kalk icebergs tonight, unless someone pipes up with some reason it won't work first.

--cn

 

[Greg Hiller]

> unless someone pipes up with some reason it won't work first.<

You are thinking about floating these in your tank? or the sump? Will these be 'dissolved' calcium hydroxide, or some type of slurry? I don't think it's a good idea if you plan to use a slurry, as the introduction of undissolved calcium hydroxide to a tank is in general a bad idea.

 

[gordonzoo]

Frozen RO/DI would be OK to put in to bring down temp. I just freeze a 2-liter and put the entire frozen bottle in the sump like most of the rest of us that don't have a chiller. With your Idea of introducing frozen Kalk, I don't think it would dissolve slowly, it would be gone in a matter of minutes thus spiking the system. To build on your idea you need something that would dissolve s l o w l y, something like a chlorine tab.

 

[conrad]

You are thinking about floating these in your tank? or the sump? Will these be 'dissolved' calcium hydroxide, or some type of slurry? I don't think it's a good idea if you plan to use a slurry, as the introduction of undissolved calcium hydroxide to a tank is in general a bad idea.

Ain't got no sump, it would go right in the display. This is just my usual kalk solution that I would dump in sometime in the morning when the pH is low. You know, the clear stuff taken from the middle of my kalk reservoir. It did appear to freeze fine, and doesn't look like it separated or anything else weird. I'm fully prepared to go for it in a bit.

Thanks for responding though! I wanted to run it by the chemistry geniuses here in case there was some weird thing that was going to happen at the state changes at the liquid/solid boundary. Since I haven't heard anything I'm going to go for it and I'll let you all know how it turns out. Maybe I'll make a new thread though with a better title so that people have some idea what's inside.

--cn

 

[conrad]

Frozen RO/DI would be OK to put in to bring down temp. I just freeze a 2-liter and put the entire frozen bottle in the sump like most of the rest of us that don't have a chiller. With your Idea of introducing frozen Kalk, I don't think it would dissolve slowly, it would be gone in a matter of minutes thus spiking the system. To build on your idea you need something that would dissolve s l o w l y, something like a chlorine tab.

Right, frozen RO/DI would obviously be fine for makeup water. But I use kalk for makeup water, not plain old RO/DI. Hence my idea. I'm floating a ziploc baggie with ice cubes in it in my 5.5 gallon nano right now, since there's not enough room around to float the 16-oz soda bottles I froze for the purpose. Oh well, I can use them in the bigger tank if necessary.

As for dissolving slowly, no it wouldn't be slow like a drip, but it would be slower than what I normally do, which is just pour it in. So this would be a (small, perhaps) improvement in my kalk delivery method.

Your idea of some sort of slowly dissolving kalk tablet is interesting, but I have no idea whether it can be made or if it would work. That's beyond my intuition, so I'll defer to the chemistry geniuses and the DIYers for that experiment.

--cn

 

[conrad]

kalk icebergs ...

Well, I did it and it worked just fine. It took about eight minutes to melt and brought the temp down a degree or two. I'm going to keep doing this until they turn on the AC on the 15th. I did discover this morning that the hottest point in the day for my bedroom is much earlier in the morning than I had thought. I'll put the kalk iceberg in earlier tomorrow. I was kind of saving it for a temp emergency, but once the sun gets high so it's beating down not in, and the breeze kicks up, I'm OK.

--cn

 

[mano1192]

Conrad what exactly are u using for your "slurry", I need to start adding kalk as well cause my PH is getting toooo low in the am right when lights come on..... UGH it would be soo much easier to just leave a light on at night over the sump... if i only had a sump..

 

[wrassefan]

why not just go on Craigslist and look for a "free" ac unit. at least you know the room will be cool...and the tank...

 

[gordonzoo]

Since it's no more than you usually dump in at once then I say why not. Good Idea. I thought you were replacing a drip.

 

[conrad]

I'm not using a "slurry", I'm using a "solution". In other words, there's no undisolved solids in it. I'm using the expensive but presumably high quality stuff from the LFS that's marketed for aquarium use. There are tons of cheaper sources of calcium hydroxide though. I'm just taking the usual amount of kalkwasser I need to replace evaporation and freezing it first. Then in the morning instead of pouring in room temperature kalk from my kalk jug, I float the kalk iceberg in the tank. Serves multiple purposes.

I have a standalone AC unit from last summer when the building system failed and they were waiting for a crane date to get the new mechanical unit on the roof. But it didn't work very well. I've got a lot of big windows that you can't mount a normal AC unit in. The ones they gave us were big floor standing ones, but for whatever reason didn't work well. In chatting with one of the longer term residents here today, he said that in the past he'd talked the building management into switching the building system from heat to AC earlier than state law allows (June 15th). So I'm hopeful that I'll have good AC early this week.

The kalk iceberg actually works well. It dispenses kalk more slowly than simply pouring it, and I think the temperature difference helps disperse it, due to convection currents. I saw that it was getting mixed better. When I just dump it in it tends to float near the top for a bit.

--cn

 

[Randy Holmes-Farley]

Thanks for responding though! I wanted to run it by the chemistry geniuses here in case there was some weird thing that was going to happen at the state changes at the liquid/solid boundary. Since I haven't heard anything I'm going to go for it and I'll let you all know how it turns out.

The Ca++ and OH- will be excluded from the ice, and will precipitate as solid particles of Ca(OH)2. Whether that is a problem or not depends on how much you add, but if you started with clear limewater before freezing, I'd expect it is OK.

 

[conrad]

The Ca++ and OH- will be excluded from the ice, and will precipitate as solid particles of Ca(OH)2. Whether that is a problem or not depends on how much you add, but if you started with clear limewater before freezing, I'd expect it is OK.

Ah, thanks, that's the sort of thing I was looking for! I'm using a 16oz container's worth of clear limewater, and it seems to be working fine. There's no obvious precipitate if that would be visible to the naked eye. The pH goes up the same as when I pour in room temperature limewater.

The kalk icebergs seem to work fine. But I've been forced to open my shades during the past couple of days and the ambient light is enough to bring the pH up more than usual, so I couldn't use my regular kalk dose (which I'd frozen into a berg) this morning for fear of spiking the pH too much.

Thanks again for your help!

--cn