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
 

[diywannabe7]

Would your response apply equally to cast iron baths regarding paint?

[MitchellMc]

Welcome to the Bunnings Workshop community @diywannabe7. It's terrific to have you join us.

No, cast iron baths do not suffer the same issue as they are solid. Provided you scratched up the existing surface, you could apply a standard exterior water-based paint, which, when cured, would be harmless to animals.

Please let me know if you have any questions.

Mitchell
 

[diywannabe7]

Thanks so much for your welcome and response. Would exterior water-based paint hold up to a fish pond though? Cheers

[EricL]

Hello @diywannabe7 

The exterior water-based paint is not meant for permanent immersion or to be used in immediate proximity to a body of water. It would be best to use the Crommelins Pond Seal as Mitchell suggested. 

If you need further assistance, please let us know.

Eric

[MitchellMc]

Hi @diywannabe7,

I'm sorry for the confusion. My response about using a water-based exterior paint would be for the outside of the bath. For the inside, being permanently submerged in water, you'd could really only try the Pondseal. Even then, you would need to do a test section to ensure it binds adequately to the what I would presume to be a painted surface.

Apply the product, wait 72-hours, cut a cross through it with a retractable knife, place clear tape over it and then pull the tape off rapidly. If the tape doesn't pull the product off then it would likely be fine to use.

Mitchell