PH Controllers

[Ballabooyeah]

Just wanted to know if anyone has purchased a PH COntroller from Ebay?
They are around £35 - £50 - seem cheaper than what is in the stores but are they worth it. I am talking of the PH - 201 model. Also there is a CE certified one which is £70 or a non certified one for £35.

Just want to see if there is any bad reports before I jump in and get one.

Thanks

Andrew :roll:

[Macca]

Andrew I strongly believe you get what you pay for. I personally would look out for a second hand aquamedic one (lots out there since the introduction of aquatronic) and maybe buy a new probe. What ever you do make sure and calibrate it and check the calibration regularly until you trust the readings.

James

[subz88]

Hi Andrew,

be wary of the non CE approved items. They are illegal to sell in the EU, and if you ever get into a situation where something nasty happened an insurance company would ditch you as soon as they found out.

I design electrical systems for a living and can guess that the guys selling for £70 paid a good few thousand to obtain the CE certification required. FWIW I recommend them for good service.

I'm not 100% certain but I think the Aquamedic controller is a rebadged PH-201.

As with all of these items, "you pays your money and you takes your choice" :wink:

[liquidlogic]

can someone tell me how they work ??

[subz88]

can someone tell me how they work ??

Hey Liquid ;)
Do you mean implementing Nernst equations on a microcontroller or how a pH electrode functions? Or what a pH controller is intended to do?

[liquidlogic]

i ment wht is done to the water to stablise the PH. i know the PH controller must add or do sumthing to the water. both wud be helpful lol

[subz88]

i ment wht is done to the water to stablise the PH. i know the PH controller must add or do sumthing to the water. both wud be helpful lol

Controllers measure the pH level of the water, and most modern devices can be set to switch off or on whatever electrical device is connected to it.

For instance, if you are using it to run a calcium reactor, a solenoid valve would be attached to the controller. When the pH increased above a preset level, the solenoid would be opened by the controller to allow CO2 to enter the reactor, and produce carbonic acid and reduce the pH back down again at which point the solenoid valve would be set to the closed position.

Another use of pH controllers could be to prevent a spike in pH as a result of excessive kalk addition, if the pH rose above a preset level, the feed to the kalk stirrer could be switched off as a precaution.

A controller isn't used to stabilise pH in the tank usually. Maintain the correct alkalinity level in balance with your calcium, and ensure that there is plenty of surface agitation and the room is well ventilated to reduce any CO2 buildup. It's CO2 and that is usually responsible for low pH in an aquarium.

[liquidlogic]

ahhhhhhhhhh thanks mate :grin: