I’m very interested in pool monitoring.
Finally, would you recommend it?
Thanks a lot for this answer, seems this only zigbee option for pool monitoring is a nogo 
@t3k @cloudbr34k you need to re-calibrate device before use. Also water needs to be above 20°C to get correct data (25°C when calibrating!) I did all possible calibrations PH, ORP and EC and data seem fine so far. Need more time for testing.
I found out that device needs some time to measure all correctly. Specially PH needs more than 1 minute. You can see that in app when you open it, it usually starts low and goes up to final measurement. Because of that when using Local Tuya integration there is need to bump device with switching repeatedly “backlight_value” to 0 and back to 1, which keeps device up.
i was told that you dont need to recalibrate it should be calibrated when you get the device.
Are you referring to water temp when calibrating or in general
EC was not calibrated for sure, I even did not get EC calibration liquid with the device. I recommend calibration and it needs to be done at 25°C!
Also see my previous post that device needs some time to get to final measurement, which was mine issue in daily use. I set HA to keep asking the device for measurement for 2 minutes every 30 minutes. See low value drops at the beginning of each measurement.
how did you set HA to ask the device?
Setting “backlight_value” to “0” and back to “1” repeatedly in automation.
Sorry are you using zigbee or wifi version?
ZigBee over Local Tuya integration from xZetsubou.
Thank you for your response
Hi Sikita
My PoolMeter is now working with the Tuya xZetsubou fork. But I dont get updated values and the trick with the backlight isnt working.
is this correct configured?
{
"friendly_name": "Backlight",
"entity_category": "None",
"restore_on_reconnect": true,
"is_passive_entity": false,
"device_class": "switch",
"id": "104",
"platform": "switch",
"icon": ""
},
{
"id": "105",
"entity_category": "config",
"min_value": 0.0,
"max_value": 100000.0,
"step_size": 1.0,
"restore_on_reconnect": false,
"is_passive_entity": false,
"friendly_name": "",
"platform": "number"
}
See my configuration below. I never tried higher 'max_value", could be time of sending data back in seconds? Just an idea, try that.
{
"friendly_name": "Temperature",
"entity_category": "diagnostic",
"unit_of_measurement": "\u00b0C",
"device_class": "temperature",
"state_class": "measurement",
"scaling": 0.1,
"id": "2",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "Battery",
"entity_category": "diagnostic",
"unit_of_measurement": "%",
"device_class": "battery",
"state_class": "measurement",
"id": "7",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "PH",
"entity_category": "diagnostic",
"device_class": "ph",
"state_class": "measurement",
"scaling": 0.1,
"id": "10",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "EC",
"entity_category": "diagnostic",
"unit_of_measurement": "\u03bcS/cm",
"state_class": "measurement",
"id": "11",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "ORP",
"entity_category": "diagnostic",
"unit_of_measurement": "mV",
"state_class": "measurement",
"id": "101",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "Chlorine",
"entity_category": "diagnostic",
"unit_of_measurement": "mg/l",
"state_class": "measurement",
"scaling": 0.1,
"id": "102",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "Salt",
"entity_category": "diagnostic",
"unit_of_measurement": "ppm",
"state_class": "measurement",
"id": "117",
"platform": "sensor",
"icon": ""
},
{
"friendly_name": "Request",
"entity_category": "config",
"min_value": 0.0,
"max_value": 1.0,
"step_size": 1.0,
"restore_on_reconnect": true,
"is_passive_entity": true,
"id": "105",
"platform": "number",
"icon": ""
},
{
"id": "103",
"friendly_name": "PH Standard",
"entity_category": "diagnostic",
"platform": "sensor"
}
yeeeaah - it seems as it works now!
Have you tried higher “max_value”, any effect?
oh sorry - didnt tried that. After it works my thoughts was “never change a running system” 
I have tried with the fork version of local tuya, and it connects to the hub, but does not show any devices in HomeAssistant.
I am considering how much effort it is to add it directly to Z2M. There is a similar device, which some settings could be borrowed from.
UPDATE: It was easy to just copy that device above a new device called YK-S03, with new fingerprint (‘_TZE200_d9mzkhoq’), and then I got all values into zigbee2mqtt and into home assistant. However like the old device, it set to update every 10 minutes. I will make an PR to the repo later
UPDATE 2: I have now added the device directly to my Zigbee2MQTT, and it works great with my MR. I am fetching data every 5 minutes and there is no lack of data. Its mostly the temperature which changes, which is actually a good sign.
Thank you guys for building this post, but I am pulling my hair out with this one.
I installed the xZetsubou/hass-localtuya And it is able to discover my devices. When I go to add the pool monitor and discover “entities Automatically” I get an error “An error occurred: Couldn’t find the data for your device category: szjcy”
Any ideas? Thanks
I had exactly same problem, so it found it easier just to add the device directly to my existing zigbee gateway together with Zigbee2MQTT.
Hi Jesper,
I assume your solution uses a generic zigbee usb dongle to pair YK-S03 with your home assistant configuration.
If this is the case, may you please recommend a zigbee usb dongle that works correctly with this?
Thanks