Monitoring pH levels... how ?

[Adrian Brentnall]

Could do - but then I'd have to watch the security camera..... I was looking for a 'you're about to run out' alarm. The alarm bit's easy - it's the sensor that's bothering me

[Adrian Brentnall]

Could do - but my life's not that organised...

[Adrian Brentnall]

Again - not likely to win me too many 'brownie points' if it goes off @

2am.... - and not really a 'you're about to run out' warning....

[Adrian Brentnall]

I see that probes on their own are available - don;t know what sort of output they give, and whether they can be left immersed continually ? I was looking to see if any of the 'aquarium' stuff had alarms, but couldn't see one that did (cheaply!)

[Adrian Brentnall]

I'm not that organised! Water usage tends to vary winter vs summer with watering in the polytunnel..

[John Williamson]

As someone else suggested, mount the alkali container on a spring supported plate with a microswitch attached to operate an alarm of your choice. I've used a similar (non-electrical) device to check on the contents of Calor Gas containers in the past. Effectively, it's a cheap, not very accurate, scale.

Or set a calendar reminder on your phone or computer to visually check the level every few weeks.

[Adrian Brentnall]

I'm not an 'organised' sort of person re diaries. Life happens on a day-to-day basis here - not that much routine.

You';re right about the pH meter solution though - by the time the pH has gone up then it's too late - thinking about it - it's some kind of advance warning that's needed - which is probably another level switch in the dosing chemical....?

[Adrian Brentnall]

Had thought about that as a possibility.... platform, big spring, microswitch - might just be the simplest way. This stuff is very dense - so mechanically there'd need to be some kind of safe (? metal) platform for it to sit on...

[Adrian Brentnall]

There's already one float switch as part of the dosing system - but it simply stops the dosing & lights the tiny led - doesn't do anything 'useful' Any switchery needs to withstand the seriously alkaline environment...

[Adrian Brentnall]

You're right - that's what it does. Need to catch the fact that the tank is 'soon going to be empty'

- to prevent the blue bath syndrome.

[Adrian Brentnall]

..but the light's 'too late' - by the time the text had arrived by bath will be blue, and I'll know!

[Adrian Brentnall]

Yes - but I don;t really want to be drinking water that's pH5 - which is what it indicates without the dosing...

don;t start me on lead!

[Adrian Brentnall]

a 'digital' scale - no less (on/off !) I've a friend who is a metal-basher - it's a possibility...

Opaque container - can't see the contents..

[Clive George]

Set something to email you every month reminding you.

[Onetap]

The last one I used, the float contained a magnet slid up & down on a rod that contained a reed switch.

There are also floating bulb types, the switch is activated when the bulb dangles on the connecting lead.

All sealed against hostile chemicals.

[Nightjar]

According to the data sheet, the standard version of these will work in alkali, neutral or mildly acid liquids:

Colin Bignell

[Nightjar]

I can empathise with that. I rarely know what day of the week it is or the date. However, if you aim to check it once a month, you should manage to achieve at least once every three months, which is all you really need. :-)

Colin Bignell

[Archibald Tarquin Blenkinsopp]

Hmm! you drink the stuff? Do you chlorine dose as well?

If you want a none invasive detector use s two wire proximity switch for your caustic container.

AB

[Mathew Newton]

And end up with foul tasting water. Not to mention the high cost of a suitably sized unit and ongoing maintenance.

[Mathew Newton]

Float switch into side of container?