Dosing pump setup questions

[Bandit13]

I bit the bullet and ordered a jebao cp-4 dosing pump yesterday since manual dosing is causing to large of a swing in parameters.

Since I've never had a dosing pump I got some simple questions regarding the setup.

1)can you install the dosing pump below the dosing location? For example can I install the pump in my stand then run the dosing tubes up to the tank above? Will the pumps have enough power to dose like this once they are primed?

2) would the pump work if I installed it vertically oriented were the pumps would be under the body of the dosing unit? This would be instead of horizontally mounted were the pumps are facing the front of the unit.

 

[dannyp02908]

They are peristaltic so orientation should be fine and pumping up and over should be fine one you run it long enough to get the solution through the line.

 

[phg1960]

I use a Marine-Magic doser which is basically the same. I believe that the manual stated a max lift of 6', so you should be fine. Definitely put check valves on the output though. Even if not submerged, without the check valves, the outputs are will siphon back a bit making it difficult control the expected output. I keep the valves on mine right at the tubing holder with only two inches of tubing after them.

 

[JohnK]

One thing to keep in mind is that if the tubing wears out / starts leaking on the pump head, it will siphon back if the pump is lower than the supply. This is a big issue with the old aqua medic peristaltic pumps, they wear out the tubing pretty quickly and then have a habit of leaking on themselves and then in turn frying the pump drive.

 

[reef87]

I use a Marine-Magic doser which is basically the same. I believe that the manual stated a max lift of 6', so you should be fine. Definitely put check valves on the output though. Even if not submerged, without the check valves, the outputs are will siphon back a bit making it difficult control the expected output. I keep the valves on mine right at the tubing holder with only two inches of tubing after them.

why would you need a valve? do they even make check valve for 1/4" tube?
why should it be siphoned back when not submerged?
I am sorry I am new but I dont think that siphon issue would ever occur.

 

[JohnK]

why would you need a valve? do they even make check valve for 1/4" tube?
why should it be siphoned back when not submerged?
I am sorry I am new but I dont think that siphon issue would ever occur.

It depends. With peristaltic pumps, if they only have 2 wheels/pinch points back flow can be an issue. If the pump has 3 or4 wheels/pinch points then they are usually highly resistant to back siphoning.

In general, since they are dosing pumps back flow can be a concern because, say for example, if you're running fairly small doses each time the pump is cycled on then the volume of a few feet of tubing (that you may or may not lose to back flow) could make a significant difference to the actual dose delivered.

 

[phg1960]

Even with the 3 point pump, I still see some back siphoning without the check valves and, as John stated, the little bit you loose in the line is enough to affect the actual dose. Use standard airline check valves.

 

[JohnK]

Yup, and unlike everything else in the saltwater hobby, check valves should work fine for this application because they won't actually be exposed to saltwater and the various things growing in it.

 

[Bandit13]

Are the airline check valves an online purchase or can you find them at Home Depot and such?

And great info, thanks everyone. If anyone else has input I'll gladly listen.

The pump is scheduled to come in Monday so I'll let post how I end up setting it up

 

[Bobbofin]

Check valves

Are the airline check valves an online purchase or can you find them at Home Depot and such?

And great info, thanks everyone. If anyone else has input I'll gladly listen.

The pump is scheduled to come in Monday so I'll let post how I end up setting it up

You can buy at most LFS and even Petco and Petsmart. Got mine at Petco.

 

[johntan]

I've had this 4 channel jebao model for three months, siphoning hasn't been an issue. Reliably doses 1ml at a time for me, very happy with it.
The only thing I will say is if the unit is installed vertically, the lines coming out of the pump may pinch.

 

[Bandit13]

My dp-4 came in Monday and I got everything setup and finished running the last of the tubing tonight. Everything went smoothly and I am happy so far with my purchase. Setup and calibration were painless. The only gripe I had was the broken English instructions but I did a quick web search and found better ones.

Decided to set the pump in one of my stand cabinets on the middle shelf with the reservoirs below and tubing running out the back. I used 5/16 outer diameter vinyl tubing and three 2-liter Nalgene bottles as my supplement reservoirs.

I drilled one hole in the Nalgenes for the tubing and then two tiny holes as vents on the other side to prevent a vacuum forming. Running the tubes through the shoulder instead of the mouth will make refilling easier as the tube is out of the way and better secured in the container.

I am running mg/alk/ca through 3 channels. I have my supps diluted with ro water and the dosing volumes set so that they roughly account for my evaporation rate, so it also serves as a auto top off.

I'll be keeping an eye on my parameters for a week or two until I know everything is fine tuned. I'm gonna also wait to see if check valves will be needed if back siphoning becomes an issue, so far so good.

The unit with reservoirs


Also made a quick tub holder
Before:


After:


Thanks again everyone for the info, made setup easier knowing what to expect!