Hi Bumble Bee and welcome to GoY. If this is a new pond I would expect there to be problems with the colour of the water as to the frogs... lucky you!

The green stuff is living on the chemicals in the water. when they have used it all up the water will clear - but it may well be next year so be patient. If you change the water you'll have to start all over again. Baley straw is supposed to help clear it. I tried it but would have needed several lots to clear mine so am just biding my time.
The frogs would not be there if the water was unhealthy.

the green is healthy so not a problem . if you want it clear put a lilly in it .

It also stops the water from evaporating in this hot weather which they keep telling us we are having.

My bird bath also has a thick green film on it. The birds don't seem to mind.

I don't think the lilly helps much in the first year though- I have quite a big one and mine is still green - better than it was earlier on though.