Do Optical Sensors Need Light?

[Reefing102]

Alright so due to algae growth in the back chamber of my BC32, I’m having a lid designed to cover it. However my ATO uses an optical sensor. Since almost all light will be cut off from the rear chamber, will the optical sensor still work?

Apologies if that’s a dumb question

 

[Uncle99]

Not dumb
Will work fine, mine does in dark

 

[Malcontent]

I think they produce their own light.

 

[TX_REEF]

yes, they're called optical sensors because they use a self-produced beam of light. It'll work just fine in the dark.

 

[mues]

They measure refraction, as long as the chamber isn't tinted glass you should be fine

 

[Reefing102]

Thanks! The baffles and the front are plastic/acrylic (I think the back may be black painted glass)

 

[Aquaddictorbj4]

Don't worry. Optical sensor works with their own light in the sensor. It works even better in the dark.
It might be malfunction if there is direct infrared light or sun light to the sensor.