Some subscribe to the thought that Marimo balls "shed" cladophora algae. Yours seems to be doing just that. This is an extremely difficult algae to eradicate. Since you don't have any fish, and it's a small tank, just throw away every single thing and start over. Pitch the gravel, decore. Cladophora algae loves to grow on gravel and wood/resin ornaments. Scrub that acrylic tank carefully to remove all trace (acrylic scratches easily).
If you don't want to throw everything out, at least remove everything you can part with(definitely the moss ball). Scrub everything else bi weekly and scrape the algae off manually. Yes, pluck it off the plants. Black out the tank, cover with towel, turn off light. Some suggest over dosing excel, but never tried it personally. You can bleach some types of decore and plants.
Get a sponge filter to help with some water movement. Yes a betta can handle the "flow" of a sponge filter. Plus they are less than ten dollars, including air pump, and shrimp love to pick at them. Indian almond leaves are another good purchase for a betta. Also, even though bettas don't produce much waste for their size, betta food is a water fouling champ, so make sure you still do weekly water changes with a gravel vac. Remove any uneaten food immediately. Don't rely on the shrimp to "clean" the tank.
Those white things look like seed shrimp, which are harmless as I understand.
If you don't want to throw everything out, at least remove everything you can part with(definitely the moss ball). Scrub everything else bi weekly and scrape the algae off manually. Yes, pluck it off the plants. Black out the tank, cover with towel, turn off light. Some suggest over dosing excel, but never tried it personally. You can bleach some types of decore and plants.
Get a sponge filter to help with some water movement. Yes a betta can handle the "flow" of a sponge filter. Plus they are less than ten dollars, including air pump, and shrimp love to pick at them. Indian almond leaves are another good purchase for a betta. Also, even though bettas don't produce much waste for their size, betta food is a water fouling champ, so make sure you still do weekly water changes with a gravel vac. Remove any uneaten food immediately. Don't rely on the shrimp to "clean" the tank.
Those white things look like seed shrimp, which are harmless as I understand.
And yes, they commonly go by the name of seed shrimp.
