"Critical Popperian" wrote in message
om...
Our tiny pond off our patio (50 gallons) has greenish water...

snip

More plants! More plants! More plants!

I agree. The reason there can be a green bloom in the water is that there
are sufficient nutrients in the water for algae to grow. The nutrients come
from either the fish in the water, or from fertilizer in the plants potted
in the water. The solution is the reduce the amount of plant food in the
water.

1. Feed fish less.
2. When fertilizing potted plants, use tablets into the soil rather than
soluble fertilizer into the water.
3. Use lots of floating plants such as Parrot's Feather.

It may take some weeks to reduce the food load in the water, but it will
eventually clear up.