Diy-co2 and ph-controller

[Raven_]

Hi, going to add diy-co2(yeast) to a small tank(40litre) and use a ph-controller.
The problem is it has a builtin magnetic valve and i dont want any exploding bottles in my home so wonder what would work best.

Use a overpressure release system so co2 can be released to the air when the magnetic valve is closed or rebuild the ph-controller by replacing the magnetic valve with a relay to control a pump which controls how much co2 is dissolved.

I have the knowledge required to replace the magnetic valve with a relay but prefer not to do it if a overpressure release system can easily be built.

Regards

 

[jcardona1]

this is interesting, i have never heard of using a controller of valve to shut off DIY co2. has this been done before? id be curious to see how it works. i know nothing about DIY co2, im a pressurized fanatic

 

[tylerperkins]

pics if you have any so we can see what your workin with

 

[cassharper]

I've seen a solenoid hooked up to a timer used on DIY. I can't remember what type of solenoid, I think it was the type sold for hydroponic grow systems (y'know for your... veggies and stuff).

I think it's a little overkill personally. Just hook an airstone to a pump and timer and have it run when lights are off. Outgassing of CO2 at night=no OD on CO2 and tons cheaper.

 

[Raven_]

this is interesting, i have never heard of using a controller of valve to shut off DIY co2. has this been done before? id be curious to see how it works. i know nothing about DIY co2, im a pressurized fanatic

I have seen it done with a ph-controller that can switch a 230v load such as a magnetic valve or in this case, a pump.
When the pump is off the co2 floats to the surface but when the pump is on it dissolves co2 in the water and it works quite good for a mediumsized tank.
Unfortunalty my ph-controller cant switch a 230v load as the magnetic valve is builtin the unit.

pics if you have any so we can see what your workin with

http://www.turbokeu.com/myfishtank/pict0072.jpg

I've seen a solenoid hooked up to a timer used on DIY.

Its builtin and "cant" be used without the controller, i could take it out and use another powersource but doubt i have any suitable 24volt psu.

 

[Raven_]

Drawn up a simple overpressure release system.
When the magnetic valve is open co2 will go down to a pump in the tank at a waterdepth of 5cm.
When the magnetic valve is closed co2 will instead go through a T-connector and then to the waterbottle, the hose will go all the way down to the bottom of the bottle at a waterdepth of atleast 25cm.
Oneway valves will be used to prevent any backflow from the waterbottle when the magnetic valve opens.
Any thoughts if and how it would work?

 

[Neophyte]

I have always wanted to do a controller with DIY CO2 always thought about using something like a balloon as storage.

 

[Raven_]

Okay have an update, i hooked it all up with an airpump and the air flowed as it was supposed to, in the tank when the magnetic valve was open and into the waterbottle when the magnetic valve was closed.

Yeasterday i started a real life test with diy-co2 and works good sofar, the only problem is the backflow.
When the magnetic valve is closed co2 is released in the waterbottle but 25cm of the hose gets filled with water when the magnetic valve opens and a large amount of co2 is pushed into the reactor.

I guess the backflow would be a good thing if the reactor can handle the gasvolume that comes when the magnetic valve opens, however i have an simple reactor so the pump is almost filled with gas and barely manages to get going again.

The reactor is the top half of a small bottle, roughly 150ml in volume.
Using an aquel 350L/H pump with a hose on the inlet and a spong to filter out debris.
The hose have 2 holes drilled in, one for the co2 and the other one is to recirculate gas from the reactor to the inlet of the pump.
If i should continue with this i will design and build a more efficient reactor.

Ph have been lowered from 7.1 to 6.0 in a ~20litre test-tank.
Will let it run for atleast another week and check ph from time to time to se if the ph-controller can keep it at a steady level.

 

[mgamer20o0]

ok.... let me be the first to ask why?

 

[Raven_]

The best answer would be in the line of why not? and because i can.
All i had to buy to test this was suger and yeast, to use pressurized co2 i need to spend atleast another 200€.