Yes, JW, I believe it's fine algae, although some of it is maybe 4" long ... it just billows out from the sides and everything. It's covering the lily pots, but those are growing now, and emerging from the algae, so it will all take time to balance out.
Yes, that's a hand pump, Betta, and I WANT to make it a small spitter/waterfall, but so far have not gotten that done. LOL With the wind I get here, I'd have to be very careful to use it on the edge, as the winds can easily blow the water right back out of the pond.
I did hook up my waterfall tonight. I scooped up about 2 gallons of "dirt" from inside the skippy filter, all nice and dry and looked like topsoil! Just kind of banged the bags of scrubbies and tubing on a wall to get most of the stuff off of them, and tossed them back into the filter. The water coming up through it was crystal clear. The low part of the waterfall is a "pool", and water stood in that all winter with no movement, and was a little stagnant ... duh! So, I turned on my aerator for a while to add some oxygen to the water as that water gets freshened up.
The koi were extremely happy with the warm temps this morning and sunshine. Me, too!!! That is a hippo that I got for Christmas, and it's floating right where I normally feed the koi. They were picking at it, and I told them to keep it clean. LOL