Mangrove swamps should spawn tropical fish and pufferfish

In recent snapshots, the mangrove swamps have been added. I would like to suggest that tropical fish and pufferfish should be able to spawn in these biomes for a few reasons:

First off, in reality mangrove swamps are quite important habitats for reef creatures, as these habitats provide valuable breeding and nursery grounds for hundreds of reef-associated fish and invertebrate species.

•In addition, there are a wide variety of fish species that chose to make mangrove swamps their permanent habitat, as the roots provide shelter, and the trees and currents provide nutrients.

•Since Minecraft has been on a trend of bringing light to environmental awareness, bringing awareness to the importance that mangrove swamps have on aquatic species into the game, may help bring awareness to that in the real world as well.

Second, for gameplay reasons, adding fish into the biome can help make the waters of the biome more lively. Although there's bees, frogs, and slimes populating the land, there isn't much life to be found within the water itself - a decent portion of many mangrove swamp biomes.

•As wild/naturally spawning tropical fish and pufferfish count for the ambient water creatures spawn cap (they don't effect the spawn cap for typical animals or monsters, and they shortly despawn without player interactions due to them being ambient mobs), adding these fish to the biome wouldn't really effect game performance in any negative way.