Last week, when I visited a customer at their lab, I met a man who refused to perform serial dilutions in any other way than with tubes.
He was used to them and although it took a lot of time and effort to prepare them, he had worked like that for 10 years and had no intention of changing.

It turns out that when I showed him the Dilucup® System he got impressed:

-“It's clear that I could save a lot of time with Dilucup®” - he said. And he continued – “But I don't understand the colour code, what is it for?”

I explained that the red Dilucups were the ones that had been diluted and plated in the previous sample. The orange ones are those ready to be plated from the actual sample and the green ones those to be used in the next sample.

-“But I only see 2 different colours and I will get confused. I am colour-blind, you know, and this does not work for me.”

-“No problem” - I said.
Then I changed the colours.

He chuckled.

-“Wow, this changes everything. Now I can see the 3 colours!” - he said.