What size pump for my water change?

[OffRoad322]

I want to start pumping the dirty water from my tank to a drain 45ft from my tank. I'm sure like everyone I'm tired of lugging buckets.

What size pump would I need to do this? Not sure how to calculate this.

I was thinking something like the Cobalt MJ1200. This has 295GPH and max 69" of head pressure. Sounds good but not sure it would pump the water to the sink drain.

 

[mcgyvr]

How fast do you want to pump it and what is the vertical height from where the pump will sit to where the tube exits

 

[OffRoad322]

How fast do you want to pump it and what is the vertical height from where the pump will sit to where the tube exits

I would like to see if pump pretty fast to make water changes quick...the tank is 60inches high to the top of the tank on the stand.

 

[ryeguyy84]

Is the drain on the floor? If so just get some 3/4 inch tubing and start a syphon. You can use a small pump to start the syphon if you don't want to suck on the tube.

Sent from my SM-G950U using Tapatalk

 

[lapin]

Get yourself a Danner 18 = 1800 gph. Will make for a fast empty. Plus they can handle your head pressure. That Cobalt MJ1200 is not going to be fast at all if it will even work. First time your suck some sand with it you will not be happy.

 

[mcgyvr]

I would like to see if pump pretty fast to make water changes quick...the tank is 60inches high to the top of the tank on the stand.

How fast is quick?

And I asked the height difference from where the pump will be to the outlet of the tube pumping water.. Thats head height..
Sounds like the outlet (sink) is actually lower than the pumps location (but I'm assuming) so you essentially have zero or negative head in which a siphon will start and any pump will do that..

 

[_Mackus_]

I want to start pumping the dirty water from my tank to a drain 45ft from my tank. I'm sure like everyone I'm tired of lugging buckets.

What size pump would I need to do this? Not sure how to calculate this.

I was thinking something like the Cobalt MJ1200. This has 295GPH and max 69" of head pressure. Sounds good but not sure it would pump the water to the sink drain.

MJ1200 will work. I use the same pump for this same purpose. Not pumping quite as far as you, but probably similar head pressure (from near the bottom of my tank, tube going over the top, and then 20 or so feet to my kitchen sink). It's slow...takes about 7 minutes to pump out 16 gallons. But I've got a pretty narrow tube so even with a more powerful pump it still takes similar time. If you're going to hard plumb in some wider tubing, 1" or more ID, and leave the pump in your tank, then I'd use a different pump. Danner Mag12 could be a good choice.

 

[dtapke]

yeah, you'd need to know the head height which is the distance in upward elevation from the level of the water to the drain. Also at distances of 45' you'll want to increase the diameter of the tubing used as a smaller diameter tubing will run into pressure loss over distance as well.

forgive the bizarre link, but this gives some good resistance numbers for tubing.

https://www.homebrewersassociation....ng-act-how-to-balance-your-home-draft-system/

you'll note 3/8 vinyl tubing provides an additional .2psi/ft of resistance, so over 45 feet you'd have 9 psi of resistance

whereas 1/2 vinyl tubing you would only have 1.125psi of resistance