...we had one measurement unit, that did both KH and other parameters, with a single dosing pump unit.

I would happily pay the combine price of the two units, if it was made as one.
I don't have space for another four units, but I'd love the features. I already have four units from GHL, so I'd need space for a whopping 8 units!

I know you like to build stuff thats modular and the customer can pick and mix, but honestly, just giving us a consolidated solution would be far more value for many reefers.

Eight units would need an entire cabinet on it's own and it's bigger than my monster PC case.

Eight units and four of them would be dosing pumps (KH pumps, IOND pumps, elements pumps and ATO/WC pumps), thats just silliness.