Questions about Auto water change Challenges.

Austinswill

New member
Hello everyone. I am afraid this may be long winded but I will do my best.

My tank is a 140 with a total system volume of 120 gallons. My current auto water change setup is an Auto Aqua unit. I have two 55 gallon tanks in a closet behind the tank which serve as a new salt water (NSW) reservoir and one that serves as a waste tank. Right now I do not have a way to access a drain without going up about 10 feet and the pumps for the Auto Aqua simply will not pump that high. This is why I have the waste tank. I have safety measures in place for all the possible failure modes and have a high confidence in the system.

The 55 gallon NSW reservoir requires a refill every 20-22 days.
I have a 5 gallon ATO reservoir to which I add Kalkwasser. I have to replace this about every 5 days. I have a calcium reactor on the way so KW will no longer be needed.

Anyhow, I would very much like to change the system up a bit. I would like to access a drain line and change the wastewater tank to a RODI tank. This would make it so my water making activities only happen once a month. This would be great for ULM and also make it easy for me to leave town for longer periods, which I certainly do as I travel for a living. My wife is usually home but there are times we will vacation.

I have been considering the new Versa pumps to drive my Auto water change. However in thinking through how the system would work, I have a few concerns.

The Idea would be to use one pump to pull water out continuously and the other to put water in continuously. However with no central management, this to me seems like a very dangerous setup.

-Should the output side fail, for any reason. Line plugged, tube exits water, pump fails, line cracks, ECT...I would have incoming NSW which is connected to 55 gallons which could flood the tank and home. I could prevent inflow with a float valve, however I do not know if that is acceptable with a peristaltic pump.

- should the INput side fail: Pump fails, line pulls air, line clogged... I would have water being pumped out of the tank with nothing to replace it. This could result in the sump pump running dry, heaters being exposed and obviously that is not acceptable. This seems like the easier problem to solve by simply putting the intake tube for the old water only about an inch deep. This way if the water level dropped in the sump, the out water line would eventually suck air. However I do not know if peristaltic pumps are self priming ( I THINK they are but am not sure) or how high they are capable of doing so. Additionally, if a line cracked I would have a 55 gallon tank slowly being pumped into my home, with no safety measure to stop it. The Auto Aqua will not do this as it has a timed safety measure in place.

-Lastly, there is the issue of balancing IN vs OUT flow. I know the pumps can be calibrated, however with the changing level of the NSW reservoir, I suspect the amount of NSW that is dosed will change slightly. I see no way to perfectly balance the In/out of this type of system. I could probably get close, but I suspect I would see a drift in salinity that would need to be corrected on some regular interval. With the Auto Aqua, this is not an issue.

So, the basic questions are:

1- Can a float valve be used to stop the flow from a peristaltic pump?
2- Will a peristaltic pump self prime and if so, to what height?
3- Does anyone using peristaltic pumps with no central management have issues with the system not being perfectly balanced for in/out ? How do you deal with that?



EXTRA- I have a second solution which may be the best and cheapest for me. I have considered having the Auto aqua pump the wastewater into a 5 gallon jug which would be located in the equipment closet. It only does 2.5 gallons a day. I would put an overflow prevention on this jug. I could then use a peristaltic pump to drive that water out of the jug and up 10-12 feet and laterally 15 feet to put it down a drain. Should that pump fail and the jug fill the overflow prevention should shut off the flow from the Auto aqua. At that point the auto aqua would stop and sound an alarm. This would also be problematic as if I was away when it happens there would be no way to remedy it remotely. This however seems like the safest option for my home and a fairly reasonable risk level to the tank.

I am also aware that a Neptune system with water level sensors would solve these issues, It is just not in the budget right now.


Any additional input you guys have would be great.
 

Austinswill

New member
I forgot to mention... Even with the solution for "in" side failure... putting the out side pickup slightly below the water line poses problems as well. What would happen is the ATO system would fill the sump back up to the normal level, the out side would pump it out and the cycle would repeat which would crash the salinity and likely the tank.
 

ryeguyy84

New member
I got to the versa portion then stopped to offer this. Just get a dual head peristaltic pump like a Cole Parmer. I've had mine setup pumping water from my basement for AWC. Every once in a while I make sure it's calibrated and it always is. It's a bit pricey and not all that quiet but for me it's in the basement so I can't hear it. On one head I have a connection to a 55g drum for NSW and then the other side runs to the tank upstairs. The other head sucks water from the sump then down to the basement and over about 25 feet then back upstairs to the drain on the kitchen sink.

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Austinswill

New member
I got to the versa portion then stopped to offer this. Just get a dual head peristaltic pump like a Cole Parmer. I've had mine setup pumping water from my basement for AWC. Every once in a while I make sure it's calibrated and it always is. It's a bit pricey and not all that quiet but for me it's in the basement so I can't hear it. On one head I have a connection to a 55g drum for NSW and then the other side runs to the tank upstairs. The other head sucks water from the sump then down to the basement and over about 25 feet then back upstairs to the drain on the kitchen sink.

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Thank you, however that solution still has the vulnerabilities I mentioned. I am glad it is working for you, but I leave town regularly and need it to be failsafe.
 

ryeguyy84

New member
I have a low and high float hooked to my apex break out box. If one triggers AWC stops until I tell it everything's okay.

The low is just below my ATO switch and I added a 15 min delay to my ATO so I'm theory it should trigger before the ATO kicks on.

Can you change the pump on your AWC system?

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Austinswill

New member
I have a low and high float hooked to my apex break out box. If one triggers AWC stops until I tell it everything's okay.

The low is just below my ATO switch and I added a 15 min delay to my ATO so I'm theory it should trigger before the ATO kicks on.

Can you change the pump on your AWC system?

Sent from my SM-G973U using Tapatalk

I have not found a pump that would be able to do 12 feet of head pressure. What would be idea is a peristaltic pump that the Autoaqua unit could control. Then I could jsut use that to push the water up and over to a drain. It would be basically the same as what I have.

I think it is a 12 v dc output.
 
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