Toilet Newbie

Hello there

Just a quick one, when I have been studying the Thetford manual you have to put a specific measure of pink stuff with 2 litres with water and pour it in the small hole above the cassette toilet.  Looking into the "hole" I can see a couple of wires on the left hand side, will it be same to pour it in or should I use a hose pipe so that te wires dont get wet?

We are venturing out this weekend on our first 3 night stay away, staying on a CL site so the toilet will be used.

Any tips or suggestions would be greatfully received.

Thanks

Gary.