PaulS:
As a seasoned developer, I would agree. It really doesn't seem that OP is a seasoned developer, though. So, when the code that actually works turns out to be completely different from the original plan, that's not surprising. Everyone goes through that. That's how you learn to plan better.
Does OP mean Old Pr*ck? I beg your pardon, I resemble that remark. I represent your insinuation. 
I knew exactly what I wanted. I knew exactly what were the inputs and the outputs (although I did add the 4 extra sensors when I realized I could test the heaters for functionality in the wake of actual heater failure and dead fish).
My only problem was to learn enough about the Arduino programming environment to get from there to here. Fortunately, I was able to copy and paste some of the difficult parts. The rest of it was just trying to choose among the "pluther" of techniques available. I didn't always (usually) choose the best. Oh, well. On to the next project.
This is more fun than sex and only half as messy.
John