This is patch 0.5.4, adjusting the core gameplay mechanic to fit more into an incremental game.
Changes:
Removed fish hunger cooldown. They can now eat as much as they want.
The feeding tool and assistant now drop more food for the fish, scaling with the level.
Fish bags now correctly display the fish growth state.
Selling fish now adds its income to the XP bar. This ensures that selling low-value high-income fish is just as valuable as selling high-value fish.
Rainbow fish base rate in 1000$ shop: 0.1% -> 0.05%
Bug fixes:
Fixed a bug where baby fish may get stuck, unable to reach the food.
Fixed a bug where the assistant might not feed the fish if there are multiple tanks on screen.