Light through reservoir cover, too much?

Just finished harvesting a grow (will post about that separately) and this time remembered to do some testing before jumping into the next grow. The inner corners of the reservoir cover have some brown crud that seems to have embedded itself into the plastic, no amount of scrubbing gets rid of it - it looks like it grew into the corners, my thought is because that’s the easiest part of the plastic structure to permeate due to the bend (and also seems to affect occlusion of light for same reason).

One of the pieces of advice that I’d not tried yet was to “check for light leaks”. My original thought was, as this unit is specifically designed to be run “as-is” then most constraints should already be accounted for (such as light penetration through the reservoir lid). What I discovered gave me a slight shock, though, so any advice would be great – particularly whether or not you are thinking “yeah, that’s nothing” or “whoa, that’s a lot of light” after watching it.

I’ve also included a pic (at end of video) of what I did to get it so black. This will be the parameter I change for the next grow unless it’s determined that the light shining through isn’t really a big deal.


Great idea!

1 Like

I couldn’t get the video to work but I think its a great idea too! I have wondered why my reservoir stays so hot even when my house is freezing. And how my roots turned brown when I never expose them to light.

Fixed the link, thanks for mentioning it wasn’t working!


Was there any sound though? What are the materials used? I am excited for the results of this find and will be watching :eyes: to see if it helps!

No sound except the scuffle of open/close the lid and grab the camera afterward. :tv:

The outer black material is just “tool box liner” cut from a roll and it’s taped to a piece of a cardboard box so it will bend/curve to make a seal when it’s pressed down onto the top of the reservoir cover.

I used an article of clothing to simulate the cocopod blocking the hole.

This is just a view from inside the res when the grow light is on with the door open (mirror not reflecting) before and after. My expectation was that there would be a pinhole of light shining through and it’d need a small piece of tape to cover it. When I removed the bottle guide on the older unit it left two holes that I covered with black tape, so I figured perhaps the nute bottle hoses were letting a bit of light in.


I just wonder if it will do more damage than help considering the plastic harboring moistness.

1 Like


Light through reservoir cover, too much?

((#RootsDoNotLikeLight)): :thinking: :astonished:



Search results for 'roots don't like light user:stephen' - AllGrowers Forum | Hydroponics, Harvesting, Cannabis, and more


1 Like

Good point @Bplatinum9, I should waterproof it


Good catch, maybe we can spray the underside with matte black Plastidip. It’s waterproof and can be peeled off with no damage to the unit. I’ve used them on my apartment faucet knobs & even my old car. And spraying the underside keeps the top of the lid nice and white so that light can still bounce off of it.