Long pump run

[Jason Judd]

I'm setting up an Auto Top Off (ATO) and Auto Water Change (AWC) using reef-pi. I have the reef-pi figured out *well, pretty much...*. The trick is, I'm pumping from my garage and I'm looking for advice and help on the buildout.

It's a 50 ft run with ~7 ft of head height. I set it up initially using a doser on a 1/4 Inner Diameter air hosing through my crawl space up to the sump. For the AWC tank water out, it's going to the sewer down in the crawlspace. However, the high volume and head height of the system makes it go through doser pumps. I'm upgrading the reef-pi to make it smart(er).

The ATO is dumping 144 ml an hour (0.91 gals a day), so pretty low volume. For the AWC, I'm thinking I'll pump 5 gal in/out every 7 days.

Questions:

1. I've had problems with my airline hose getting brittle and cracking. Is there a type of hose I should use? And what size, should bump up to 1/2 inch? Should I PVC it all the way??? I'm leaning on yes so it 'never fails'.
2. From this, I need to calculate the head height from the drag for the 50 ft + 8 head height to then select a good pump. (I have a 7.5 head height 650 gph pump that I don't think will do the job?)
3. For the AWC tank water out, I have it going into the crawlspace and tapped into my sewage line. I'm assuming I should use a pump and not rely on a gravity feed (it will have a solenoid valve). At the same time, I probably don't need a very big pump b/c the gravity feed is going to pull on it. Any thoughts on this? It's a negative head height of ~10 ft (+ ~20 ft run)

Thanks!!!

 

[Reefing Madness]

 

[Reefer Reboot]

Okay, let's take a shot at this, but first we'll need a little clarification.
When you said, " However, the high volume and head height of the system makes it go through doser pumps." are you saying that the force of the siphon is pulling water through the pump? If yes, what kind of pump is it? (IE, peristaltic, diaphragm, centrifugal.) If it is a peristaltic pump this should not happen and you will need to fix the pump. (not enough squeeze from the rollers on the internal pump head tubing.)
When you said, "For the AWC, I'm thinking I'll pump 5 gal in/out every 7 days." are you thinking of gradually pumping 5 gallons over the duration of seven days or doing it all at once every seventh day?
Now for your questions,
#1) Is your airline getting brittle and cracking in your crawl space? Does your crawl space experience freezing temperatures?
#2) If you are using good peristaltic pumps and doing this gradually over the duration of seven days then the flow will be so slow that the friction tare (head loss) of the vertical section will be inconsequential. Even the vertical head will be inconsequential because you will calibrate the pump after it is plumbed in.
#3) I would suggest paristaltic pumps to maintain water in vs. water out equilibrium.
Hope this helps some, I'll keep watching.;Watching

 

[Jason Judd]

Thanks for the reply.

Its a peristaltic pump. For ATO its a 7 min run per hour. For the water change it takes over 2 hours each. Initially I thought this would work, but then when I went through two heads, I figured my long run was what was burning the pumps out. But you're saying that the peristaltic pump is the way to go, which means all my current questions don't matter and I need to figure out why I'm going through pumps. It's not the pump motor but the 'plastic spinners' that are going out.

This was helpful. I'll do some research and see what I can figure out.

 

[Eldy]

This is going to sound a little dumb but if you have a 50ft horizontal run under the house. Just slope the pipe by lowering the far side 3/4 down from the source. So gravity helps it run the 50ft of horizontal run then you just need a pump that can push the head height.

Or if you can get from the garage to the attic then you would just need to pump up the head height at one side 10 ft or so and then slope the pipe and chase it down the wall.

 

[Reefer Reboot]

Theoretically it wouldn't matter how much higher or lower than the tank you pump the water in these cases due to the siphon suction effect of the downward slope. The head would still be the difference between the pump outlet and the water level of the tank (assuming the pipe outlet is under the tank water level).
But still not dumb, it's how we learn (and I've done a lot of "learning" in my life!)

 

[Eldy]

Reefer you just gave me the answer..... Run the line out of the tank up to the ceiling in the garage then back down to where ever you need to connect to the 50Ft run and up to the tank. Once you fill the 50ft line with water up to the the top of the tank that water will even out and act like a Pee-trap for a drain. Then you just need a pump to go up the head height of the garage ceiling.

The water in the 50Ft run will equal out until you add more water from the garage side which will cause water to flow out on the tank side because it tries to equalize the water height.

 

[MaddyP]

I’ve used Stenner double head peristaltic pumps for runs longer than this if you’re looking for an equipment recommendation.

https://stenner.com/products/pumps/double-head-adjustable-chemical-injection-pump/