pressure auto top off=fail safe limewater

A number of RC members use it, but one drawback is apparent in the decription:

"The NURCE replaces only the amount of water lost, even though the evaporation rate may vary. The current version can replenish fluid at a rate of up to 5 gallons per 30 minutes. "

So if the water level drops due to a water change, or a leak, it will replace it rapidly. With freshwater, that might be OK, but with limewater, you might cause a crash by having a leak.

It appears to just be mechanical siphoning that controls the water flow.

I've never used one, and I'd be a little suspicious that with a big density difference between the tank water and the replacement water, there might actually be flow even when no evaporation took place, and even a little tank water getting into limewater will make a mess.

I'd have to defer to folks who have actually used one to know if that is an issue or not.
 
My take on it is its just a syphon that you suck out water to get it started. Once the syphon is started the other hose is pressurized because its submersed below the water in the sump. But the water syphon stops as long as its under the water. When the water evaporates the water level drops allowing air to be drawn inside the container. The difference in pressure inside the box causes the air to enter and the water to flow out, stopping when the water level rises again. Sound correct??

Anyways, why spend money on an electric dosing pump when this can be done without it?

I thought you might be intersted in this because of your little mishap regarding a limewater overdose :D

Think this would perform the same as your setup, without the float valve to gum up and mechanical pump to keep it going?
 
<a href=showthread.php?s=&postid=6581586#post6581586 target=_blank>Originally posted</a> by Randy Holmes-Farley


So if the water level drops due to a water change, or a leak, it will replace it rapidly. With freshwater, that might be OK, but with limewater, you might cause a crash by having a leak.


I think if you were to do a water change just close a valve on it so it does not drain, untill the job is done?
 
Yes, that works for water changes, but not leaks.

But the water syphon stops as long as its under the water.

My theoretical concern is that siphoning may still happen even with the inlet underwater due to density differences. And even if that doesn't happen it may well not, I've never heard anyone complain about that), that some small amount of tank water does get entrained into the air inlet and goes into the reservoir with the air. That seems more likely to me, and wouldn't be optimal. But again, I've not heard anyone actually complain about that.
 
Do you mean leak as in aquarium leak, from silicone failer, or air leak from the hose sucking in air?

Do you think this would work for any size water container? The biggest size they have(they cant make them anymore for some reason,probably patent legalities.) is 6.6 gallon container. Should work for even a 20 gallon acrylic box also, correct?
 
Actually for the people using your 2 part recipie, this could be made:

<img src="http://i5.photobucket.com/albums/y178/salwaterfish123/diy2partdosing.jpg" alt="Image hosting by Photobucket">


Light blue is filled with calcium chloride water(calcium part), and dark blue is filled with baking soda water(alk part). Then, as they both drain(in separate sump areas, to avoid calcium carbonate, they provide the same benifets of kalkwater, without manuel dosing!haha. The black are unscrewable caps to re-fill,of course air tight. And the top hose is for air to enter thats submersed below the water in the tank. This would also be worry free if aquarium water were to enter!

I will try this, and post some pictures,my cousin has some scrap acrylic that I can use!
 
Do you mean leak as in aquarium leak, from silicone failer, or air leak from the hose sucking in air?

Anything where tank water ends up on the floor. Neve rhappened to you??? :D

I can't see size being a limiting factor, but I've neve rused one. :)
 
get a doser much better.I got the aqua medic for Randys two part,works like a charm.The tunze works great for the kalk.Has the fail safe switch so no problems.Pacific coast has a kalk stirrer that looks good but since I have the tunze there is no point for me to buy it.Aqua medic can also dose kalk or auto top off water.I don't see why you want to go through the problem of making something and then worry what if something goes wrong with it.I don't see this hobby being for the poor.I only see it making people poor.
 
Thx for the advice Steve! :)


Randy,

Does this water top off device work this way:

Water is filled into a sealed container, with limewater or your choice of alk maint. One hose has to be syphon started by you to get the drain going and water flowing out from the top off. As long as the air intake hose is submerged below tank water the weight of uplifting aquarium water traveling up the hose will stop any further drain of top off water. The syphon temporarily stops because no air can enter anymore. But when tank water evaporates past the point to allow air into the "air hose" again it will release air pressure inside the box allowing the water to drain again untill the sump is full and no air can enter the sump hose. Sound correct?

How would it stop water from re-entering the top off container? Pressure?

Maybee easyer with a picture

<img src="http://i5.photobucket.com/albums/y178/salwaterfish123/f901f17c.jpg" alt="Image hosting by Photobucket">
1 is stopped, 2 is runing, 3 is stopped.
 
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check valves allow water to go threw but stop water from back flowing.Back water valves prevent water from coming back aswell.You would have to rely on no air getting into the setup to keep that syphon stable.Your drawing looks correct but like I told you before pain in the *** to do this setup.You have to control that syphon but it will work.As long as you get air for the syphon and you are able to stop the syphon at your third point you are fine.What if you get some are bubbles or debris in the tubes?If the container is higher and you are using syphon pressure it will make it hard for your tank water to return and flow back into you container.what happens when your alk container runs low.Will you get a better chance of losing syphon and risk losing it or having a stronger syphon and having whats left of your alk formula spill into system.Every time you add the alk to replenish you run the risk of adding bubbles to the system.I don't know what that litttle box is at the bottom of your drawing(left side of tank)
 
<img src="http://i5.photobucket.com/albums/y178/salwaterfish123/kalktopoff.jpg" alt="Image hosting by Photobucket">

I made the top off. Items include:
-5 gallon bucket of instant ocean with the lid
- some 1/2" latex tubing
- 1 kent float valve
- silicone to seal the gap, or get some bulkhead fittings, for extra profesionality look.

The clear tube attached to the bucket "sucks in the air". The blue tube drains out water. When the valve closes, it stops the drain of the water! When it opens a little, the blue tube starts to drip.

This desighn is much better than the other one they make. It can not suck in water from the tank into the bucket because the float valve closes when it gets tight enough! So I will have no problems dosing kalk water with this.

It works the same way as theirs, only difference in functionality is Im using a float valve for added saftey of contamination. The water level sits about 2" from the float valve, so not a drop of water can enter the bucket. Kalk cannot get contamintaed this way.

Works GREAT! :D Cost=free(I had all the stuff already)


Sent you a pm Randy :)
 
How about that? The Nurce is back in production. I had one that I used on a previous tank, but just for freshwater topoff. The likelyhood of a catastrophic leak is fairly small. The Nurce occasionally stopped working because air got into the siphon line somehow, breaking the siphon.

I am now using a Tunze Osmolator, which works quite well. It is much more fish-sitter friendly than the Nurce. I had to teach fish-sitters how to refill the Nurce before leaving for vacation.
 
drawing looks good and like you said cheap to make.I thought of going that way but I didn't have the room.If I had the spce it cost nothing to make this doser.
 
<a href=showthread.php?s=&postid=6639488#post6639488 target=_blank>Originally posted</a> by dougc
How about that? The Nurce is back in production. I had one that I used on a previous tank, but just for freshwater topoff. The likelyhood of a catastrophic leak is fairly small. The Nurce occasionally stopped working because air got into the siphon line somehow, breaking the siphon.

I am now using a Tunze Osmolator, which works quite well. It is much more fish-sitter friendly than the Nurce. I had to teach fish-sitters how to refill the Nurce before leaving for vacation.

The reason for air entering it is because the output for H2o delivery needs to be submerged below the water line.If the line is allowed to have air enter it looses pressure, wich allows the water in the tube to completly drain out.I did not detail this in the drawing. The water tube should be submerged to work correctly.

Yep, it simple and works. With nothing to screw up. Perhaps the air intake may one day need cleaning. Or the float valve would get a snail stuck in it and stay open. But as you said, failer is minimal :)
 
<a href=showthread.php?s=&postid=6646619#post6646619 target=_blank>Originally posted</a> by steve the plumb
drawing looks good and like you said cheap to make.I thought of going that way but I didn't have the room.If I had the spce it cost nothing to make this doser.

You can make it from a smaller container :) Still wondering how this would work hooked up to an RO feeding it H2o all day. Who knows.
 
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