View Full Version : Nielson reactor?

01/22/2006, 12:21 PM
Will using a NIELSON reactor for Kalk dosing make a significant difference as comapred to just throwing Kalk in the top -off water bucket?

01/22/2006, 01:18 PM
There are some differences, but the basic effects are similar. Both will raise the pH, alkalinity, and calcium. The Nielsen reactor is set up to dose a saturated lime solution, and you can make the same strength solution with topoff.

The topoff approach has some advantages. You can tune the strength of the solution more, and by letting the kalk settle after mixing, some contaminants will precipitate out of solution. Also, vinegar can be added to the mix, for various effects. The Nielsen reactors are somewhat less time-consuming, though.

This article might be useful:


Randy Holmes-Farley
01/23/2006, 05:04 AM
In addition to those differences, it is sometimes hard to get the limewater saturated with reactors if you allow it to settle at all.

I prefer to dose from a reservoir, but if you are pressed for space, a reactor can be useful. :)

01/23/2006, 08:58 AM
<a href=showthread.php?s=&postid=6564376#post6564376 target=_blank>Originally posted</a> by Randy Holmes-Farley
In addition to those differences, it is sometimes hard to get the limewater saturated with reactors if you allow it to settle at all.

Help me understand your statement Randy. Why would it be hard to get the limewater saturated with reactors if you allow it to settle? If it's already mixed and saturated, and it's not exposed to air, how would it lose it's saturation?

Randy Holmes-Farley
01/23/2006, 09:05 AM
When new water enters, if you do not stir (to dissolve more solids) before any of that water leaves, then it has diluted the potency of the effluent.

01/23/2006, 09:12 AM
I've noticed more of an effect from a kalk reactor vs. standing container of kalk.

Randy Holmes-Farley
01/23/2006, 09:19 AM
More of an effect on what?

01/23/2006, 09:28 AM
On levels (alk. Cal.) It's brought my Alk. up about 1dkh, where with the standing container, it was maintained 1dkh lower.

Randy Holmes-Farley
01/23/2006, 09:33 AM
My guess is that, assuming the standing container had saturated limewater, that the reactor was dosing particles as well as dissolved solids, so was not just limewater.

01/25/2006, 01:42 PM
It is quite possible that I did not mix the standing container well enough. I was putting in more kalk than needed.

I've collected a couple of samples straight from the reactor after letting it settle the 1 hour after mixing and i'm finding no 'particles' in the doses.

Randy Holmes-Farley
01/25/2006, 02:29 PM
Huh, OK, I don't understand it then unless the standing reservoir was less than saturated, or dosed in smaller amounts. :)

01/25/2006, 04:28 PM
I just throw in a lot of Kalk in the reservoir and let it do the auto- top off. Do I need to do some mixing too?

Randy Holmes-Farley
01/26/2006, 04:56 AM
It depends on the reactor design, but many won't dissolve much of the lime without stirring. If it is maintaining alkalinity in your aquarium, however, it is doing fine. :)

01/26/2006, 05:25 AM
Alkalinity and pH are running low and I am adding 2 part solutions to bring it up.

Randy Holmes-Farley
01/26/2006, 06:15 AM
I'd check the effluent and see if anything is dissolving into it. Conductivity is the best way, but pH can also work. IT may not be dissolving much at all without stirring.

This article describes more about using limewater:

What Your Grandmother Never Told You About Lime