Poor Mans Auto-Dosing

[magicmagni]

*** Final Design on page 2***

I'm wondering if no one else has thought of this before?

I found a way to automatically dose my micros using an air pump and a bubble counter. I had all the items on hand already so it really didn't cost anything; however one can probably set forth and rig this up for around $40+-?

Let me explain:

Air pressure from a standard aquarium pump is used to pressurize a fert solution into a backwards confiigured bubble counter. This pressure forces the solution into the tank. The "drip" rate is controlled to a point with the air pressure from the pump- this is sort of like a "coarse" adjustment. The "fine" adjustment is done with a standard valve on the fluid side of the line. One can fill the bubble counter with the total amount of traces they want to dose for the week then add distilled water to fill the bottle to where the neck starts. I generally find a drip rate of 1 drip every 30-60 seconds will empty the contents of the bottle into the tank within a week, but I recommend one experiments with plain water first to get an idea of how it works.

I've been running this system now for about 3 weeks and must say I am quite pleased although one of the tougher things for me is getting the drip rate just right with the standard air valve on the fluild side. This has made for quite a bit of tinkering to get just right, but overall I think it's a feasible alternative to some of the other methods out there.

Let me know what you all think. Any questions?

[turtlehead]

any pictures of this? I'm interested.

[briandmiles]

Yeah, the devil is in the details so post everything you can think of. All the parts you used. Where were they originally purchased and how are they all hooked up? Do you use a timer? Can you supply a drawing or diagram? If this idea can be refined to the point that it is reasonably predictable I can see a lot of people using it.

Brian

[m.lemay]

I like the whole idea a lot.

The only difficulty I see is getting it to be reliable and accurate to a degree. Post up some pics, so we can all get an idea of exactly what you got going on, and maybe we can refine this thing online.

Marcel

[m.lemay]

Heres a quick sketch of what I think this contraption might look like.

[BlueRam]

Could this be done with gravity feed too?

[bharada]

Originally Posted by BlueRam

Could this be done with gravity feed too?

Kent has their AquaDoser which is gravity fed using an IV-like drip tube. I'm seriously looking into getting a few of these as I'll be going on a three week vacation in August and anything that'll eliminate my brother-in-law having to touch my tanks is good.

Based on last summer's evaporation rates I figure if I empty two 5g Kent dosing containers into my 125g tank over three weeks I'll be able to dose and top off the tank in one step. Same with using two 2.5g jugs into my 40g tank over three weeks. Using two jugs over each tank also allows me to have macros in one and micros in the other.

My trouble tank is my 20g, which isn't open top (so little evaporation) and doses using PPS, so minimal daily input (1ml PPS, 1ml Excel, and 1ml TE per day). Because I don't have masssive evaporation in this tank I can't dilute the doses and dump a bunch of water into the tank. I'll need to spend a bit more time thinking about how to handle this tank.

[shalu]

I have the Kent unit. Used it once and done with it. Hard to keep the rate steady. Bought this dosing pump. Will set it up soon, probably will use the Kent container to feed the pump.

[bharada]

Originally Posted by shalu

I have the Kent unit. Used it once and done with it. Hard to keep the rate steady.

What size container did you buy? Maybe I can borrow it from you to try out? I'm not looking for precision dosing, but a semi-steady drip to last out the three weeks I'll be gone. It would be interesting to just let it run for a week to see the amount it drips.

[shalu]

it was like 2 gallons. Sure, you are welcome to try it, but the drip counter is now flooded with water. The main problem is that the adjustment knob is really hard to control, any small change there, you get huge rate change, from no flow to way too much flow.

[magicmagni]

OK, OK.... a picture says a thousand words anyways so here are some pics of the setup. BTW you got it pretty much Marcel.

Here's a pic of the air pump and bottle. I'm using the green lines. The clear ones are for something else. FYI the air adjustment valve is built into the pump.


Here's a close-up of the cap. See how I put the plastic connectors through the cap. I drilled them out slightly undersized to secure a tight fit. I didn't even have to use any sealant, but it wouldn't be a bad idea. Notice that only one line (the one that carries the fluid to the tank) goes to the bottom of the container into the fluid.


Heres a pic of the drip adjuster tank side. Note that it is a simple off the shelf valve from the LFS. Side note: Perhaps a high precision needle valve like the ones we use with C02 would work better? Or perhaps it may clog? I may have to try and see.


Dripping into the tank. Notice that the line is elevated above the water line. This does two things. It allows you to count the drops into the tank and it eliminates the possibility of water siphoning out of the tank in the event the pump goes off.


That's it for now. Fire away if anyone has any questions.

Jeff

[jhoetzl]

While I Like the idea, using a glass bottle concerns me a bit...if something causes the output to clog, you might get a nasty "incident" with that bottle, filling it with air...then again, depending on the pump, the tightness of those seals, the pump might blow first...

[bharada]

Sha,
Are you using the dosing pump only for micros? It would seem that you'd need another one for macros so that you don't get the Fe in the traces precipitating out of solution.

That means I'd need six pumps to cover my three tanks...$360 for the pumps alone. Ouch! But no one ever said keeping high-tech tanks would be cheap.

[magicmagni]

Originally Posted by jhoetzl

While I Like the idea, using a glass bottle concerns me a bit...if something causes the output to clog, you might get a nasty "incident" with that bottle, filling it with air...then again, depending on the pump, the tightness of those seals, the pump might blow first...

A plastic soda bottle could be used inplace of the glass bottle, but I really doubt that the pressure would be high enough to cause a problem.

[magicmagni]

Originally Posted by bharada

That means I'd need six pumps to cover my three tanks...$360 for the pumps alone. Ouch! But no one ever said keeping high-tech tanks would be cheap.

What's nice about the "airdoser" Idea method I'm thinking is that for the price of a "T" and some extra tubing and a bottle you can run macros too. I'm actually thinking of running another bottle for my macros, hopefully the pressure drop isn't too much...we'll see.