Aquariums: My first aquarium!

I have gotten my first Aquarium, set it up and left it for about 4 weeks. Now I just added neocaridina shrimps about a week ago. The water where I live is hard, I haven’t done any water readings so I don’t know other parameters. I have a Xiaomi smart tank, but I’m not using the smart features, not using th heater either and I’m not sure what this type of filter is called. Also have a small air stone in there

There’s plenty of bio film and Alge.

Most plants are doing good and growing, one plant looks almost completely dead but I have left it in there.

The shrimp seem healthy, two of them has shedded.

Right now there’s plenty of shrimp food just laying on the bottom and moulding, I think I over fed a bit. I guess what I’m looking for here is just some pointers on the setup and advice on how to improve.

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