What animal-safe paint could be used on a bathtub pond?

[MattS]

I have two (acrylic) bathtubs that I want to convert into frog ponds in a corner of my garden. Others in my local garden groups have said I should just use them as is and fill with rocks/pebbles, but if possible I'd like to be able to paint the bath surface for a more natural colour and look, even if just the lip of the bath that will be more visible. There are three main things I'm seeking advice on for setting this up:

1. What types of primers, paints or adhesives that would be safe for fish/frogs/birds could I potentially use for this?

2. Someone suggested adding course sand to the paint for more texture (I'm sure the frogs would like this). But maybe there are textured paints that would work as well/better?

3. An additional step will be adding a metal grate over the tubs for added safety for little kids. How could I go about securing this to the tub? (Can I drill into the tub rim, and if so what should I use?)

[MitchellMc]

Welcome to the Bunnings Workshop community @MattS. It's wonderful to have you join us, and many thanks for your question about painting a bath.

Unfortunately, no paints are designed to adhere to acrylic baths. Acrylic is a flexible material that expands and contracts, and any hard painted coating is likely to crack.

You might like to roughen the surface up with 80-grit sandpaper and then experiment with Crommelins Pond Seal. However, acrylic is not a substrate it is designed to adhere to.

You can certainly add steel mesh over the top, which you'll need to cut to size with either bolt cutters or an angle grinder. It can be fixed to the rim of the bath with U clips. I'd recommend pre-drilling the tub and screwing the clips in.

Please let me know if you have any questions.

Mitchell