Still Reservoirs for limewater delivery

[Unstable]

I got this quote from your article titled "The Degradation of LImewater in Air"

I make up limewater in a 44-gallon Rubbermaid Brute trashcan by putting the CaO in the bottom, and pouring in water by 5-gallon buckets. That process takes about 5 minutes once every 2-3 weeks. The trashcan is closed by simply putting on its lid. The pump that sends the water to the sump is a Reef-Filler pump (maximum pumping rate 3 gallons per day), which is controlled to match the evaporation rate using a float switch in my sump.

I was wondering if you could be more specific about what you do.

Do you mix the limewater and let it set before letting it enter the tank?

I'm guessing that you mix the water by pouring the water into the trash can from 5 gallon buckets. Should I mix the water with a pump or something for a little while to ensure that it is mixed well? My concern here is that I will let my RO/DI system fill the trash can, and it will probably not mix the kalk up like pouring water in from a bucket would.

Where is the water drawn from in the trash can... the middle or bottom? Does it matter?

Do you actually use all the water in the trash can into your tank, or do you end up adding new water and kalk before the bottom is reached?

Do you clean the trash can between fills?

Is there any concern with pouring limewater down the drain?

I'm sorry for all the questions, but I'm trying to setup a system similar to yours, and I just can't find the answers to these questions.

Thanks for your help,

Bryan

 

[Randy Holmes-Farley]

I have a 44 gallon trash can, with a hose leading into it that is the suction end of a 3 GPD Reef Filler pump controlled by a float switch in my sump. The hose takes from very close to the bottom.

I add the solid lime, and then pour in the RO/DI water by 5-6 gallons at a time until it is fill.

Then I use it. In effect, it is settled in a day or so, and so for the first bit it isn't fully settled, then for the next 3 wseeks or so, it is clear, with solids on the bottom, and sometimes solids on the top.

I run it down fairly far, but leave the water and solid residue on the bottom for the next round. I clean it out once a year or so.

There's no concern that I am aware of in pouring resonable amounts of limewater down the drain. Drain opener is higher in pH.

 

[Unstable]

Great! Thanks for the info. I'm going to try it out.

Is there any reason why I can't gravity feed the limewater into my sump instead of using a dosing pump?

I know the part about the float switch getting stuck and flooding, but I figured I would put in a valve to have the flow go really slow and hope I catch it before it floods too bad

 

[Randy Holmes-Farley]

You'd have to store the limewater above the tank, drill the container, and control the flow in a way besides a float switch (the float valve is a possibility), but otherwise there is no reason you can't do that.

 

[Mr_Quality]

I use a float switch (2 actually, the 2nd is a safety back-up in case the 1st sticks) and a polypropylene solenoid valve w/ my gravity feed kalk bucket. When the water level in the sump drops due to evaporation, the switch opens the solenoid and kalk solution refills the tank to the desired level.

Here are the float switches in the sump.

and here is the control box that contains the solenoid valve (I also have a power switch, green power indicator light and a yellow valve-open indicator light)

 

[Unstable]

Wow... that looks pretty sweet! I like the lights.

Thanks for all the info!

 

[daveisrael]

I have a 44 gallon trash can, with a hose leading into it that is the suction end of a 3 GPD Reef Filler pump controlled by a float switch in my sump. The hose takes from very close to the bottom.
I add the solid lime, and then pour in the RO/DI water by 5-6 gallons at a time until it is fill.
Then I use it. In effect, it is settled in a day or so, and so for the first bit it isn't fully settled, then for the next 3 wseeks or so, it is clear, with solids on the bottom, and sometimes solids on the top.
I run it down fairly far, but leave the water and solid residue on the bottom for the next round. I clean it out once a year or so.

Just a thought, if you ran a line off of your RO/DI unit (with a "T" connector) to a float valve on the trash can you keep the lime water in, you would essentially have a cheap nilsen reactor. All you would need is a circulation pump in the trash can on a timer, to mix up the new RO water with the lime.....Presto! you wouldn't need to mix up new batches of lime, just add more kalk when it gets low.

 

[Unstable]

That sounds good, but I thought that stirring the mixture of limewater would expose it to more carbon dioxide and would cause degradation over time.

Is there a concern with degradation using a pump in the trashcan?

 

[daveisrael]

As long as you have the top on the trash can tightly, I don't think that exposure to air (carbon dioxide) would be anymore than normally mixing a batch of kalk up. If you left the top off, you'd have a degradation problem.

 

[Randy Holmes-Farley]

I'd rather not stir my limewater, but instead keep it fully settled all of the time.

I also don't want my RO/DI turning on and off that frequently. It is more efficient to use them in large runs than many starts and stops, as far as I know.

 

[daveisrael]

Never heard of the RO/DI efficiency deal, it makes sense though.

I use the same basic setup that you do except with a five gallon bucket instead of a brute (it only lasts me about week though) and an aquamedic peristaltic pump. I've got a nilsen reactor on order so it just made me think.

Do you think the high pH of the limewater will degrade the tubing on the peristaltic pump faster than RO water would? The tubing is Santoprene on my pump.

 

[Randy Holmes-Farley]

Santoprene? I don't expect it will degrade in limewater more than in regular water, no.

 

[bowfront]

This method has worked perfect for me since I swithced to it from running a Nielsen. I needed more space and was looking for something very simple and fool proof and Randy's method works.

 

[reefkeeper1]

I have a 44 gallon trash can, with a hose leading into it that is the suction end of a 3 GPD Reef Filler pump controlled by a float switch in my sump. The hose takes from very close to the bottom.

Randy, and everyone else with a peristaltic pump, do you position your pump above the highest level of the top-off reservoir so that in the event the tubing in the rollers of the pumps breaks for some reason, you won't siphon everything out of the top-off reservoir?

 

[Randy Holmes-Farley]

I actually use a diaphragm pump, not a perstaltic pump. I have it just above the top of the limewater trash can. It then pumps to my sump, which is equal to or higher than the limewater. These types of pumps don't siphon, as I understand it, but since the levels won't allow that anyway, it is not a concern.

With a peristaltic pump, some siphoning might be possible, but frequently the pinch roller is tight enough to preclude it.

 

[JRoweNole]

Randy:

I, too, want to switch to your method of Kalk delivery (I have been dosing SeaChem Clacium and Alk for the last couple of years).

A couple of more questions (hopefully not dumb questions) please:

1. Does your tube running from the pump to the holding tank just sit on the lip of the holding tank with the lid on top of it? Or, did you insert some type of bulkhead in the holding tank to run the tube through?

2. I currently use two float swithes (one for safety) for top-off. A mini-jet pump is activated in my holding tank to pump RO/DI water into my sump. If I were to switch to your method, could I still use the mini-jet pump to pump Kalk into my sump, or should I go with another type of pump (Reef-filler, SpectraPure Liter Meter(or something less expensive))?

I really enjoy and respect all of your information.

Thank you!

 

[Randy Holmes-Farley]

The tubing from the limewater reservoir runs to just above my sump, and then allows the limewater to drip into the turbulent water where my skimmer outlet dumps in.

Whether you can use a powerhead for delivery depends on how much is delivered in the normal dose. Sometimes too much will be delivered before the float switch cuts off, and the pH may get really high either in the main tank, or in a sump.

Adding 1.25% of the volume at once can drive the pH up by 0.7 pH units (way too much).

More like 0.2% or less might be an acceptable amount for instant delivery.

 

[JRoweNole]

Randy:

Thank you for your response.

Regarding my tubing question, I was referring to the section of the tube going IN/OUT to/of the holding tank - does the lid of the holding tank just sit on top of the tube that is exiting the holding tank and dripping into your sump?

 

[Randy Holmes-Farley]

Oh, I see. The tubing going into the limewater passes through a slot that I cut in the trash can lid and then down to the bottom. No bulkhead.

 

[Unstable]

Adding 1.25% of the volume at once can drive the pH up by 0.7 pH units (way too much).

So, if you don't mind, lets fill in some numbers here.

My tank is 110 gallons and my sump fuge holds around 30 gallons. Take out around 30% for rock and sand, and I get round 100 gallons.

More like 0.2% or less might be an acceptable amount for instant delivery.

So you are saying that I should not add more than .2 gallons at a time?

So, what would be the range on dripping in kalk to a sump of the described system running around 600 to 800 gph through that sump?

What should the drip rate be? .2 gph? Is more ok?

What would be a good rate to add the kalk to the system?

I guess if the tank is evaporating 6 gal per day then the .2 gph will never catch up to the .25 gph evaporation rate... but if the tank is evaporating 4 gal per day then the .2 gph will pass the .16 gph evaporation rate.