Strange toilet behaviour

[Sam (Fussy_Furball)]

Have a look at wizz's advice:  http://wizz-catz.co.uk/soiling.html

[Team Svartalfheims]

It could be something as simple as them not wanting to use a tray if it only has one wee or poo in it already. Obviously if you're out at work all day then you can't clean the tray out the minute they've used it but might be worth removing wees and poos as often as you can and seeing if that helps.

Are both cats neutered?  If not then it could be a territory issue. Make sure you clean the area thoroughly with simple solution to remove all traces of the smell.

[Walter349]

My two 8 month old cats, have the habit of poo'ing on the floor in the toilet. This is located on the ground floor and is where their litter tray is positioned. They also use the tray for poo'ing. At least one of them does, and for wee'ing. When they were kittens, they used the tray all the time.

I have tried:
Separate litter trays.
Different cat litter types.
Open litter trays,
Covered litter trays.
Cleaning the litter tray out every day.
Changing the litter every other day, every day, once a week.

Fortunately the toilet is tiled. The do not do it anywhere else, except on one a occasion, when someone closed the toilet door.

Does anyone have any thoughts on this and how to correct it. In all other respects they are normal, healthy, affectionate cats