Dosing Kalk with auto topoff

[JeffersonReef]

Hello all.

I recently purchased an auto topoff (float switch). I want to dose kalk in my makeup water. Previously, I used a doser for this, and dosed about a gallon every other day. However, I have a question about dosing kalk using my resivoir and ato: how long does the limewater actually stay useful? I have seen contradictory articles... some say that it is useless after a day or two.. some say that it is good for a week or so. I plan to refill my resivor every 4-5 days or so...what do you think?

Also, since the kalk powder binds to stuff in the topoff water, why couldnt I just add more kalk than is nescessary, and have a powerhead remix the settled kalk once a day or so? If I did this, and kept the lid of the resivoir tightly closed, would this help keep the limewater effective throughout the week?

Any advice or info is greatly appreciated! Thanks all~!

-Tony

 

[Billybeau1]

A week is no problem. 2 weeks is probably no problem. You do not want to remix it once the impurities settle to the bottom. If you do remix, you will have to wait for it to settle out again.

Your limewater will remain effective without mixing.

 

[adova]

Check out this reactor - it uses a powerhead to mix the settlement:

http://www.marinedepot.com/md_viewItem.asp?idproduct=PM4111

Shawn

 

[bertoni]

http://www.reefkeeping.com/issues/2003-05/rhf/feature/index.php

That article covers the issue in detail. As long as the limewater is not stirred, it's likely to last a very long time. Two weeks is not a problem at all, in my experience.

 

[Mike O'Brien]

The reactor is sealed from air, so mixing is not a problem. With a reservoir you want it to remain still. That way a crust forms on the surface and keeps the limewater beneath fresh and block the atmospheric CO2 from entering.

 

[adova]

So, sealed you want to mix - not sealed you want to avoid mixing? The way I understood it, if you did not mix as you added new R/O water, the solution would be diluted and less effective. Also the crust would become entirely solid after a period of time.

 

[Mike O'Brien]

With a still reservoir, you are only adding and mixing once. When it's low you add more water and lime and mix again.

Inside the reactor, the incoming fresh water is exactly why it needs to be mixed.

 

[vanceny]

I'm going to do the same thing but had a question regarding preparing the limewater. I've already added the water to my resevoir, how do I mix in the kalk without introducing to much CO2?

Do I just add the amount in and let it settle or does it need to be initially stirred? And if stirred/mixed, what should I use?

 

[adova]

Well, you need to mix it initially toget the mixture into solution (about 2 tbsp per gallon if I remember correctly).

My thing is why would anyone have a manual resevoir - make it easy and Ro/DI top off the resevior and mix occassionally.

 

[adova]

Oh - and if it isn't sealed, CO2 will be introduced no matter what...

 

[vanceny]

My resevoir is controlled by a float switch but the ro/di is not close by. I fill the resevoir overnight and then wheel it over to the sump.
How much does it need to be mixed? and for how long?

Thanks for the reply.

 

[Billybeau1]

2 teaspoons per gallon. not tablespoons.

 

[bertoni]

CO2 will dissolve into the limewater over time, but that's an extremely slow process if no circulation is used. See the article for details.

 

[Mike O'Brien]

I for one feel that it is risky to have the RO hooked to the tank. I like to run the tank as simple as can be. Float switches and selenoids fail eventually and usually when you are not home. So I use a reservoir. And I feel that less impurities are added to the tank compared to a sealed reactor that is mixing constantly. Some units end up using all the powder that is added.

 

[anemoneguy]

i had a float stick while one for a day. had to replace my new wood floor.

 

[adova]

Same here - that is why I have moved to float valve and gravity feed. At the most the Kalk will build up in it and cause it to fail shut - definitely a preference over fail open

Shawn

 

[JeffersonReef]

Im only using a 5g topoff resivoir... or maybe 10g at the most. My sump currently is 55g... and I may upgrade to 100g this summer... so I am not concerned about the float switch sticking. I just want to be sure that I am getting some good limewater in my RODI! I dont have a rodi unit, so resivoir is the only way to go... besides, I really wouldnt want to risk hooking a rodi directly to my tank.... wether I was using a valve or a switch!

Thanks everyone!

-TJ

 

[Reefer Steve]

just curious, what pump will you be using for this?

 

[JeffersonReef]

the toms aquatic aqualifter.

 

[Mike O'Brien]

Me too.