Lighting through a glass top?

[VFX]

I have a glass top on my cube tank & have to wipe the underside of the glass every day.

Having a Korallia pointing towards the surface probably doesn't help too much but it gets pretty opaque if I don't clean it for more a few days.

I'm getting a bit p***ed off with it at the moment & will change it for an egg crate pretty soon & live with the extra evaporation (the tank has an ATO).

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