Trident waste pipe tap

The current setup is a white plastic tap that has broken.

Does anyone know what size hose it attaches to and where I can get a replacement?

Read earlier posts about using a washing machine tap. But these are metal how do you attach it to the rubbber hose?

Thanks

Shenn, sorry can't help with hose size. maybe measure outlet of tank then look on fleabay for hose and tap. A quick look showed quite a selection. good luck