Hello everyone! Before we get to discussing I have a river that leads to a pond that is about 150 gallons. The river part is about 4 inches deep, with rocks that have algae. The pond has lots of plants in thick patches. I have most plants around the edges and corners. I have rocks in the middle of the pond. The pond currently has 5 breeding Pygmy sunfish 2 males 3 females. The river looks really nice but I wanted a new addition that will just live in the river. I thought of hill stream loaches since they are the only fish that could live in those kind of conditions. Would hill stream loaches be able to live in 4 inches of water? Every website I check says yes and no but these are like the natural conditions they live in am I right? But just making sure thanks!!!!