Winter string alge

[Dwight]

Well probably better referred to as hair alge. I think I know the answer but I want some input from you guys and gals. Up until a couple weeks ago I was cleaning my EA Eazy about once a week. Then winter started in earnest. Now I'm up to once a day. The culprit is hair alge...the 2" stuff that populates the sides and bottom of the pond as the main component of the biofilm. My water finally went below 50 degrees about a month ago and is now hovering in the 40's. I stopped feeding in late Nov. What is causing the hair alge to shed ?

[KoiCop]

if you are still running your filtration and doing your regular water changes, but not feeding your fish, then you've probably brought your pond back into 'balance' and the algae is starving to death.

Neat, huh? Don

[RayJordan]

If your hair algae is dying and shedding it would be very easy to pluck off the sides of your pond. Give it a tug and see how firmly it is attached.

Another possibility is that since you are not feeding the koi are grazing on the algae on the walls. The algae is not vert digestable so it mostly passes right through the koi and that is what you are finding in the vortex.

[Dwight]

Hmmmmm....interesting..... Wonder if more folk are having this experience ???? Notice I didn't say problem as both cases simply represent a natural cycle in a healthy pond it seems. The water does occasionally get warm enough for the koi to move around a lot and I've seen them " grazing ". I was thinking it was starving also and it isn't stuck to the sides very strongly. I also thought the koi " grazing " would knock off much more than they would consume leaving it to pass through the BDs.

Dwight