Every morning I wake up and go the pond it has a filmy looking substance in the brown to orange color and my water clarity goes down several inches. If during the day it is windy all of this will end up on the downwind side of the pond. My aerator keeps this film from the middle with about a 30 ft diameter. If it rains it vanishes and it usually goes away by the early evening right before dark. Why does my pond fluctuate in clarity as much as it does? My visibility has been around 22 inches since I put an Alum treatment about 3 weeks ago, but today visibility was at 13 inches and it didn't improve. Most days, the water is cloudy in the morning, but by afternoon it is usually clear again. Why?

Bump. Algae, I bet.

Hard to tell. It sounds like the results of summer plankton bloom cycle. That( gooey film ) was described to me by a fisheries biologist as the cytoplasm from dead plankton (died overnight)with no light. During the day the live plankton moves to the surface for light adds O2 through respiration ,reduces visibility and dies during the night leaving the cytoplasm skim.

Maybe Bill can give us a better explanation.

Often an alum tretment will not cause all plankton to be completely removed from the water column. Alum treatment can strip out some dissolved phosphorus from the water column. Nutrients still present after an alum treatment will stimulate an algae bloom.

Film on pond in morning during a bloom will usually be one or a combination of several things. One would not know for sure unless it was exmined microscopically. It could be as ewest says but since it has color then I suspect it is living algae that moved to the surface at night seeking more light. Waves or activity will mix it below the surface until things are calm again and it moves back to the surface. When the bloom subsides the film will almost always dissappear. Various types of air pollution will settle on the pond and can cause films often grayish ones. Surface films occur most frequently in warmest months when winds are least.

Bill,

I treated pond with cutrine plus and it seemed to work on it for a couple of days, but it is back. Should I try to kill it or is it hurting anything. Will it eventually go away?

I would be extremely cautious about trying to kill a plankton bloom at this time of year. To much risk of an O2 depletion.

If this is a plankton bloom of some kind, why isn't my water turning that dark green color? Is this a different type of plankton bloom and will the right bloom eventually occur?

First all plankton blooms are not green. Some are brown , some are red and many are green and some have little visible color until they reach a high density. Plankton is there in the water but often in amounts to low to see thus resulting in an infertile low productivity pond with clear water. A pic would help a lot towards sorting this out. For example your cutrine plus application would have killed a lot of plankton and may have resulted in the plankton ooze except that you indicated that it occurs over a much longer time (every am). Here are pics of a plankton bloom succession on one of our ponds (1 early green phase , (2 secondary green/brown phase with more zooplankton and (3 late phase late season brownish zooplankton bloom ongoing as the background color and including what is believed to be a red euglena bloom.

See if this helps. This is a pic of a small scale dead plankton cytoplasm ooze from our pond blown to one side.

Eric, could this “stuff” be “dead plankton cytoplasm ooze” that you described?
I observed and photographed this at a central Kansas pond the past weekend.

Pond is ~1/2 acre, surrounded by cottonwood and willow trees with decaying leaves around shore, supposedly 12 ft deep at dam, and obviously shallow upper end.
¼ hp Gast, 2 diffuser aeration system – runs 24/7.

It's just tree pollen George.

Just kidding, it does look like some of the very infrequent algea blooms we have had at our pond. The last time we had strong bloom blowing into the bank like that we also had a BIG cold front come through and shut the bloom down which caused a localized fish kill.

George that looks like a thick plankton bloom as best I can tell. The ooze I see is not bright green like that.

Eric, would a "thick plankton bloom" indicate "at risk" nutrient rich water?

I'm treading lightly here since I "sneaked" a photo out of curiosity and my opinion was not solicited.

George what was the visibility ?

Eric, this pond belongs to a relative and as a guest, my observations were only casual.
The visability observed from about a 10 ft distance appeared to be 12+ inches and could see decaying leaves on the bottom.

I asked about water source and was told run-off and a "spring".
I suspect an aquifer because was told they ran into water when they dug their swimming pool.
Pond was mature when they obtained the property some 12 years ago.

Aeration system was installed 5 yeara ago, running 24/7, followed by a massive fish kill - I didn't want to suggest my thoughts as to the cause.
Their interest in the pond has deminished.
I saw a jewel in the rough.

George if they have 12+ in. of visibility and aeration I would not be concerned with that small amount of plankton on the surface at this time of year. I assume they are not fertilizing or feeding , have normal fish densities and have a full pond.

Thanks much Eric - I guess you are REALLY a pondaholic when you start worrying about other folks ponds...

Hey guys, all your reponses have the Pondrookie confused. My pond was about 10 feet low here in NE Texas until the rains last month. Now it is full all from the run-off. A couple of days ago it turned and looks just like the George1 last picture. Rained last night a little and it was gone this morning. Now it's back but not as bad, yet. At first I thought pollen but now I am not sure. Visability is at least 12 inches. I had read somewhere that a large run-off like we had can cause the pond to "turn-over" whatever that means.

My pond is 4 years old and has never done this before. I do aerate 24/7. This is the first summer its been full. Any additional comments would be appreciated. All my fish including Tilapia still seem healthy.

Gary can you post a pic ? If the big runoff was a mth ago then the danger of it causing a turnover is past. Your aeration should help prevent that type of turnover as your water is well mixed.

How can you tell the difference between pollen and planktonic algae?

Greetings merrilynmason:

I encountered the puzzling issue of algae or pollen in the Spring of 2012 here in Ohio (remember...the Spring o 2012 was warmer than normal and we had an early Spring). I had many many calls from a 507 acre lake association concerned about blue-green algae.

The concern turned out to be pollen. Pollen is very distinct when placed under the microscope. It has a very durable outer cover that often looks like it has spikes on it. Pollen is very durable and can last in sediments for millions of years.. Crucial in the study of ancient lakes, etc.... also known as Paleolimnology
http://en.wikipedia.org/wiki/Pollen_analysis
http://en.wikipedia.org/wiki/Paleolimnology

Attached are two photos:
1) Pollen floating in the dam outlet of a lake
2) A microscopic photo of the pollen...

Pollen on the water will most often occur in the spring when trees are flowering. Rarely do trees flower in midsummer or fall. Some surface algae blooms - scums will occur in spring such as that by Chlamydomonas which is a rich green color. Dense accumulations of pollen comes from flowers of leafy trees or evergreens, both produce pollen. Pollen will usually be a more yellowish, browinish, or pale dull green color whereas brighter green hues and reds will often be an algae. Exceptions occur. Only way to know if it is pollen or algae for certain is to look at it with a microscope as noted by J.Grey.