I'm still a relatively new pond owner, dug and stocked this spring. It's been hot and dry for my location, the pond is down over a foot with no meaningful rain since mid-July. What really stinks is that within 20 miles east and south of me they have had significant rainfalls. Anyway, the fish still seem to be active and feeding fine. I do have bottom aeration and homemade fountain (used a bilge pump idea another member posted). My question is with these conditions, anything I should keep on eye on? Or check regularly?
Something has happened to my pond in the past week. It has wavy surface scum or maybe algae but it's not green. Testing it shows Ph, nitrates, phosphates and ammonia all good. When I put it in a jar it looks clear. I've attached a couple of pictures. You can see the stuff to the right of my fountain and back by one of the diffusers. It's really only noticeable when the sun is out. Any ideas what that is?
Your light surface scums look just like mine (in the beginning). I believe it starts out as a Protozoan Scum, that feeds a green algae growth, and if no rain event or good winds occur...it turns to a bacterial thing (maybe). It all stays very much at the surface throughout its lifecycle. many times a nice breeze will come or some rain and the "stuff" goes away regardless of the phase that it is in. I have difficulty believing that it is heavy nutrients related as my pond is very new and past tests have shown no nitrates/phosphates. My theory is that without any wind/rain action that my pond develops a floating layer of pollens that feed the scum. That's all my inexperienced mind can come up with.
Here is a thread that I replied to a couple years ago that has some good links to my other "scum" threads that may be of some interest to you...
I base my assumptions on this guide. Look at page 15 for what your pond may be doing.
I still do not have a solution aside from praying for rain every few days during the hot and dry portions of the summer. I do not treat my pond with chemicals and let it run it's course.
Last edited by FishinRod; 
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