It’s fairly clear from the descriptions the Vpins that you’ve parameterised absolutely everything then created a Blynk widget for it, then rely on syncing the widget values back to the firmware for it to work.
As some of these are clearly life and death parameters for the creatures (fish presumably) that reside in your aquarium then I’d handle those bits of code very differently so that the system can function autonomously without any internet/Blynk connection, and store these critical parameters in SPIFFS.
The other parameters are just an overkill in my book, as it gives far too much control over settings that probably just need a bit of fine-tuning then can be hard-coded and forgotten about.
But, that’s just my opinion.
Pete.