In short, less food.
Or, you can get a loach or two and wipe them all out.
If you want to just remove *some*, it might be tough if they're the pond snails or the MTS's. You can hand pick them out at every water change to keep it under control, depending on how many you have (might be too much trouble).
Or, you can get a loach or two and wipe them all out.
If you want to just remove *some*, it might be tough if they're the pond snails or the MTS's. You can hand pick them out at every water change to keep it under control, depending on how many you have (might be too much trouble).