DIY kalk reactor finished and questions

[bprewit]

Ok so I built a kalk reactor with scraps and junk and here it is:
http://img.photobucket.com/albums/v358/bprewit/tank%20equipment/kalkreactor001.jpg
It is 24" tall and 4" diameter with just over 1.5g capacity and the mixing pump is some oddball type fountain pump I had that is way overkill at 600gph. My dosing pump delivers around 2.5ml through the reactor every minute which is around 1g per day. Wiring connections and timers look like so:http://img.photobucket.com/albums/v358/bprewit/tank%20equipment/kalkreactor002.jpg

Since the reactor is short and the pump too large I used a appliance timer running through a 8pin relay and a 8pin timer so it works like this: every 6hours the dosing pump kicks off for one hour to allow mixing and settling time and the mixing pump kicks on for 2 minutes. The one hour delay allows the kalk powder to settle and not dose cloudy kalk fluid to the tank. So far my ph stays pretty stable at around 8.2-8.3 throughout the day. Does this setup sound ok? Any tips or suggestions or reasons why this is not correct? Sorry I dont know much about them and just built one for grins not really expecting to hook it up.

[matt]

Sounds good; usually you mix, let it settle, then dose. I found with the kalk reactor I made, 6" tube, 24" tall, that the smallest pan world pump (180gph) worked perfect as a mixing pump; it kept the water in the reactor saturated but did not create a huge kalk storm, and you could dose 24/7 regardless of when the mixing pump was on. You might dose some KW into a glass and check for clarity and ph; if it's reasonably clear you're fine and you want a ph of at least 12; somewhere I seem to remember 12.5 being the optimal ph for KW.

I'm going to build another kalk reactor sometime soon (I hope!!) that will run directly off my R.O. unit, at least that's the plan. No dosing pump, just an auto top-off that will replace all the evaporated water in my sump with KW. I'm not planning on a high calcium demand on this tank so I'm confident the KW will maintain the tank, I'm actually worried that it might be too much and raise the ph too high. If that happens, I'll have to get a dosing pump.

[NaCl_H2O]

Matt, my Kalk doser is my top-off and it is working great. Well it was until the tube cracked around the uni-seals :( Dan's gonna build me a rectangular reactor to replace it soon.

Anyway, My top-off controller turns on a 110v solenoid which feeds the Kalk reactor (sealed), which forces clear/saturated water into the sump. When the sump is full, the solenoid closes and the mixing pump comes on for 15 minutes, then settles for the next cycle. I use two float switches (Min/Max) so that I get about 3-5g of topoff at a time. In my system that cycle probably runs about once every 6-8 hours.

I am very pleased with this setup. I use a PW40 as the mixing pump, and used one of these (http://www.smarthome.com/7279.HTML) and a couple of these (http://www.smarthome.com/7278.HTML) to build the control/timer circuit.

[NaCl_H2O]

BTW - Your DIY looks really ugly ;) but also looks like it will work!

I found that really mixing up the kalk a bit longer works better. After it settles and is clear check the PH, should be 12.5 - 12.6 if completely saturated. If not, a bit longer mixing cycle might be needed.

I have used many mixing pumps on my reactor. The paddle wheel type pumps (like a powerhead, but bigger) always fail after a short period of time. Apparently the high PH mixture is just to "Nasty" and the impeller parts break down and fail. That's why I moved to a PW pump.

[matt]

I just bought a liquid level controller and an auto shut off from purely H20 which I think will work. It was about as cheap as the DIY set up I had with a solenoid, timer, and float switch on my last tank. Steve, does your R.O. filter feed directly into your kalk reactor, or do you fill up a reservoir with water then use a dosing pump? I specifically bought a low output R.O. filter (50 gpd) with the idea that it might feed the reactor at a slow enough rate to safely dose KW. I'll find out in a month or so when I get things set up.

Cracked tube, eh? This is why I never drill the main tube for fittings, even though everyone else seems to and I get told periodically how great it works. Did you ever see the kalk reactor I built for Gator? I think it's a pretty good design and that's what I'm building for my new tank. I'm going to have left over tube to make another skimmer or reactor (I have to buy it in 5ft sections) if you have a change of heart about the square one; I don't want to take a job away from Dan, but my guess is that he's probably pretty backed up anyway.

[NaCl_H2O]

I have a 60gpd RO unit, but with my water pressure it probably does more like 80gpd. The RO/DI feeds directly into the Kalk Reactor, but remember I have a 500g+ system and this rate seems to be fine as far as PH levels go.

Actually, I like the uni-seals! I had to take the reactor apart a few times to rework pumps, etc. Stressing the hole in the tube a few times I think resulted in the crack .. then it got worse over time. I like the rectangular reactor idea - nice flat surfaces for bulkheads ;) Dan's shooting for completion this next weekend, fingers crossed!