Cheatp Ph pen vs BlueLab Guardian

[Bob's Auto's]

Or you can order this one. --> aliexpress
They even have a EC meter. --> aliexpress

Both cost approx. 20€ and have great accuracy. I can vouch for them as I've been using both for about one year now.
You'll need to buy calibration liquids separately, but those are items you can get in a local hydro/grow/aquarium store and have an expiration date...

 

[x00m]

so a little update.... i changed my reservoir today and my ph was very good before the change. was drifting down to 5.5 each morning after setting it to 5.8 the night before so the plants eating food (i think).

however, since changing the res... the ph probe on the guardian is really confusing me. if i submerg the probe all of it... in the reservoir the ph drops to 1.5... but if i take out the probe a little.. but still have 25% of it in water.. the ph shoots all the way up to 8.7 and keeps rising.

im not sure what to do... and i cant even stablize the ph because i dont know which reading is correct... i added some ph- as clean water is around a ph of 7 here... but ever since adding that ph- its been sitting at 1.5 if the ph probe is fully submerged...

the unit is brand new.. only had it for a week! and the water temps are cold because its fresh water there is a heater in there to fix that.

please help. thanks.

 

[DCLXVI]

That is extremely odd. Have you tried contacting the company?

 

[x00m]

That is extremely odd. Have you tried contacting the company?

it was an ebay purchase brand new in box. It should still have warranty i guess.

 

[DCLXVI]

Yeah, they might be at least able to help you get it working properly.

Dumb thought but have you tried unplugging and reconnecting the probe?

 

[Bob's Auto's]

its been sitting at 1.5 if the ph probe is fully submerged...

hmmm... You didn't put the probe in with cable and all did you? Because that will short out the probe.
Look at the troubleshooting guide in the manual. Maybe the answer will be in here?

 

[x00m]

Yeah, they might be at least able to help you get it working properly.

Dumb thought but have you tried unplugging and reconnecting the probe?

got it fixed... my water pump wasnt working, changed the fuse inside the plug and now the ph is stablizing.

thanks for the help anyway!

 

[Bob's Auto's]

got it fixed... my water pump wasnt working, changed the fuse inside the plug and now the ph is stablizing.

thanks for the help anyway!

Yup, stray voltage can do that as well

 

[Shadowgrows]

I cast my vote for the Aper PH20 as well. Over a year and no issues until I damaged the probe while cleaning it. Recommend not cleaning the probe after a bowl...

 

[JSH1973]

I am on my 3rd cheap PH already and it's only my 2nd grow so today I ordered a Hannah Instruments, I wanted a Bluelab like my EC Pen but they were nearly a 100 compared to 56 for this one.

HI-98103 | Hanna Instruments CHECKER1 pH Meter, ±0.2pH Accuracy, 0.01pH Resolution, 14pH Max | RS

ie.rs-online.com