That tank had a peristaltic "enteral" medical pump that fed a few milliliters of blended food each hour. The hard part is keeping the food cold so it does not spoil. I used a wine cooler, but a bigger solution is a mini refrigerator with the food inside, and the tubing running through it. You can find examples of this by googling "NPS refrigerator feeding" or "non-photo coral liquid food refrigerator".

Post what you build here