Temperature tracking and dosing

[Liftoff]

Hi all,
I am interested in building a reef-pi system.
I want to build the dosing part and would like to track temperature for now, but of course also be able to increase functionality later on.
From the tutorials that I read up to now, it seems like that for each component I buy an extra Pi Zero(?).
Is this the case? I would only like to read temperature for now and be able to do dosing.
Sorry I am a beginner and try to get first feedback before buying everything twice or not to be able to upgrade later

Best and many thanks
Liftoff

 

[Liftoff]

Ok let's change the focus a bit here and forget about temperature tracking.
I would like to build a doser with 4 peristaltic pumps using Reef-Pi.
Do I built the project twice (2xPi Zeros etc.) or can i just simply add two more pumps to the setup in the tutorial? Any information can help here
Best
Liftoff