On another thread our respected fish keeping colleague @thebiggerthebetter advised against using aluminum in/around tanks due to studies that showed the potential for aluminum to leak aluminum oxide and maybe other heavy metals into the tank, even if there are only occasional splashes etc. and not contact all the time.
Unfortunately my 2 X 325 Asian Arowana tanks both have DIY aluminum framed lids me and a couple of staff made:
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So I've decided to make some new lids just to be on the safe side, which will be similar but made with 1" PVC filled with small pebbles (and then they will be tied and strapped to the tanks). Pretty sure they won't look as nice, but that's not really a big deal, of course health/safety of fish trumps aesthetics.
I made the outer frame of 1 today, next just need to put in the rocks, and make & connect the 2 inner, plastic screened lid pieces on either side (made with smaller rectangles of PVC), which will lift up for feeding and cleaning.

I have a question though: just to improve the looks a bit I'm thinking to put a light coat of black spray paint on all the PVC -- is there any danger of leaking toxins from using say regular, household acrylic lacquer spray paint on the PVC, or is there some special kind of paint that is safer? Or likewise would it be best just not paint them?
Unfortunately my 2 X 325 Asian Arowana tanks both have DIY aluminum framed lids me and a couple of staff made:

So I've decided to make some new lids just to be on the safe side, which will be similar but made with 1" PVC filled with small pebbles (and then they will be tied and strapped to the tanks). Pretty sure they won't look as nice, but that's not really a big deal, of course health/safety of fish trumps aesthetics.
I made the outer frame of 1 today, next just need to put in the rocks, and make & connect the 2 inner, plastic screened lid pieces on either side (made with smaller rectangles of PVC), which will lift up for feeding and cleaning.

I have a question though: just to improve the looks a bit I'm thinking to put a light coat of black spray paint on all the PVC -- is there any danger of leaking toxins from using say regular, household acrylic lacquer spray paint on the PVC, or is there some special kind of paint that is safer? Or likewise would it be best just not paint them?