My 4 months old Bonsai nano tank - has the bonsai survived?

Many people have written that it's not good for bonsai because it get too much water. This is called hydroponics. Look, it's alive and well. The aquarium is 4 months old. Bonsai really thrives where they get more light. The little razboras also love this natural aquarium. I replaced the lighting with a 20 watt led. This makes it a real low tech aquarium. Minimal light, minimal maintenance. I only change the water once a week. So in the summer I struggle with Cyano bacteria unfortunately. If you have a good tip for this, please let me know.