Underwater lighting?

[brianmoooore]

Including UVc lights should help control the green growth.

 

[Midwest]

LED lights from the UK lighting manufacturer | Collingwood Lighting - https://www.collingwoodlighting.com/en/ have some good products, if expensive. They also offer advice on lighting, I believe.

 

[mhar]

LED lights from the UK lighting manufacturer | Collingwood Lighting - https://www.collingwoodlighting.com/en/ have some good products, if expensive. They also offer advice on lighting, I believe.

Thankyou for that. I have been in touch with Collingwood who are intrigued which is very promising, especially the bit about combining any lighting with UVc light

 

[mhar]

3 pictures which illustrate the reflection issue. What you can see in each is the reflection of a large stone placed across the top which had some very large bits of slate resting on it which was put there presumeably when it was covered over. The lattice work is the reflection of the frame for the roof.. If you look into the shadow of the stone you can see the lining disappearing into the depths

 

[nicebutdim]

That's a sizeable well to find within a house.