Substitue for blood when testing

[peter jones]

I am going to film dilaysis for a presentation and would like to know what i can use to show blood. I don't want to damage the machine, so can we use food colouring or any other ideas?

[John Nixon]

Hi Peter I have used milk as a substitute for blood on Gambro AK 200 Ultra S not the same colour as blood but it worked

[Chris Pearson]

Andy Mosson came up with the best blood I've ever seen which is cochineal and milk but just shunt out the dialysate side so no flow from the blood side into the machine.