Reef nutrition

Improved Cheap DIY doser

rygh

rygh

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This is not just another "cheap doser".
It actually has a feature that even expensive devices do not have.
It MIXES as well! :O
Ok, it is not critical, but the solutions can settle out a bit, causing moderate
differences in concentration as the cannisters empty.

But if that is not enough, it is real cheap, and real easy.
Costs was in the $10 range.
Probably took me about 20 minutes to build.

Materials:
Cheap tiny water pump. Like for mini-fountains.
(Suggest 12VAC pumps)
Basic 1/4" garden drip system pipe, elbows, Tee.
(Could be built with airline tubing/parts as well)
Some plastic container.
(Used munchie containers.)

How to build:
Well, look at the enclosed pictures. Pretty simple.
Basically:
PUMP -> TEE
- part of tee goes back into cannister.
- other part of tee then goes out through hole.
From hole, go down a bit, to another tee.
- part of tee goes to dripper, then to tank.
- other part of tee goes up, back through hole, and into cannister.
Blobs of silicone to seal up holes for pipe and pump wiring.

How it works:
You turn the pump on for a short time (Like 30 seconds), N times per day.
It quickly fills the tubing, and sprays back into the cannister. (Mixing)
Well, the "V" part outside of the tubing is now full. That is your "dose".
Make the V part smaller/larger to modify the individual dose. Very accurate.
The dripper insures that it drips out slowly into the tank.
It drips a bit when pump is on as well, so that does slightly affect dose.
Note: You need to drill out the dripper about every 2 months, or it clogs.

Suggestions:
I dilute my Ca/Alk about 5:1, with RODI water. I then run this about 3 times/day.

Been running for a year. Other than dripper clogging if not maintained, works great.








Attached files /attachments/sites/default/files/dosing_1.jpg /attachments/sites/default/files/dosing_2.jpg /attachments/sites/default/files/dosing_3.jpg
 
Sure.
Look at dosing_1.jpg carefully.
There is a "Y" like set of tubing in the front.
The tops of the "Y" are where the tubing goes into the cannister.
The bottom of the Y has a small circular piece, that is a standard 2 GPH drip system dripper.

The volume of the tubing in that "Y" is your dose.
The pump turns on, fills the Y, then turns off. And the liquid in the Y slowly drips out.

To adjust each dose, you simply make the Y longer / shorter.
Easiest is to cut off the bottom tube, between the T and the dripper, then cut a new tube that is longer/shorter.
Drip tubing is cheap, so easy to tweak.

To measure the dose, you trigger the pump, and let it drip out into a small vial.
The ones I have are about 10 ml.

But once you get the does roughly where you want it, you usually change how often you dose to
fine tune the amount per day.
For that, just change the timer that controls the pump, to run more/less times per day.
Note that the time the pump runs for each dose has no effect. It is the number of times it runs.
And those runs must be separated by 15 minutes or so, to make sure it all drips out.
 
I see a problem that will rear it's nasty head in no time. Those drippers clog very fast under saline conditions and as they clog the drip rate will change, thus effecting your actual dosage. So even if you drill it out every month, your drip rate will be effected.
 
That is not really much of an issue.
First, it does not really precipitate out that badly.
The solution is pretty weak. Not like it is salt water.

More importantly, the drip rate is not an important factor in the dose size.
The dose is based on the volume in the Y tubing, not the drip rate.
Ok, technically, when the pump is on, during that period, variations in the drip rate matter.
But the pump is only on for a short time. And not much drips out during that time.
So those variations over that small amount, are very minor.

Easily solved by drilling the drippers out more often also.

A bigger issue seems to be pump failure. I just had a second one die. Seem to last about a year.
Might be cheap pumps. Might be intermittent use. Or maybe they don't like the solution.
 
hmmm I thought I replied to this post... oh well.. AGAIN!

It seems to me the mixing issue allowing a more "consistent" solution might be negated by the fact as you use up solution your head height changes on the pump so it affects the rate of pumping.

Also as you mentioned a pump just died, those two part solutions are extremely dense in concentration of the product, you can very easily get precipitation(?? Calcification?) on your pumps, specifically on the shafts/impellers because that's a place where it's warmer. When I use a maxijet to mix up my alkalinity suppliment, and I use a half strength solution, the pump comes out pretty white even after only about 30 minutes.
 
Like the drip rate concern, pump rate due to head is also really not an issue.
Really - The dose is based on the volume of the "Y" tubing.
These other things have fairly small affects.
Also, you can make the uncertain effects a smaller percentage by using a larger dose size.

Good point about the pump calcification. Or Alkification?? :)
Pump just died, and I have not had time to fix it. I will check.
 
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