DIY PAR meter for $230

[clown99]

Got the idea from others on YouTube. I built LED lights with bluefish controller for my biocube 29, but I have no idea what the PAR is. But I don't want to pay $500 for a PAR meter. So I gathered the ideas from others on YouTube. Total cost is $230.
Apogee SQ-120-ss sensor $188 ($8 extra because I do NOT want the connector) + $15 shipping
https://www.apogeeinstruments.com/sq-120-ss-electric-calibration-quantum-sensor/Phone bendable holder stick $11.99 Amazon product ASIN B07951WKV6Digital multimeter $11.29 Amazon product ASIN B01ISAMUA6

I cut & shaved off the end piece of the holder stick to mount the SQ-120 sensor.
BTW, I use 1.5" heat shrink tubing to hold the sensor leads against the phone holder stick.
Then I hot-glue the open tubing end as you can see below to keep water out of the tubing.

The sensor comes with very long lead wires so I have to wrap it around the clamp end of the phone holder stick.
I strip the multimeter leads and connect them to the sensor leads with Wago connectors. They are easy to disconnect and reconnect.
BTW, the clear lead of the sensor is open, not connected to anything. I just hot-glue the end of it.
Then I velcro (All hail to velcro and duct tape, we are not worthy in their presence) the multimeter to the end of the holder stick.

To measure the PAR, switch the voltmeter to 200mV DC. Then multiply whatever reading by 5 to get the PAR results.

 

[robbyg]

I did the same thing but I must warn you that using a low cost volt meter may not give you precise readings. Check the specs on the meter and see how precise it reads voltage in the mV range. It may or may not be good enough for what you want to achieve.

 

[fltt]

Thinking of doing the same. How did this work out for you?

 

[User1]

Could have saved you 30 or so dollars. Seneye Reef is a dang good par meeter actually and it gives you an out of water monitor if you keep it in your sump. Affordable reach back alert not to mention the 30 day ammonia slide. Well worth the money.

 

[fltt]

Thank you . I will look into the Seneye.

 

[User1]

Thank you . I will look into the Seneye.

All good. I didn't mean to take away from the DIY side of it :) Great job on that btw.

I think BRS did a series on the Seneye. Link below - hope is correct. Have a great day!

https://www.bulkreefsupply.com/video/view/brstv-investigates-what-par-meter-is-the-best/