Pond Boss Forums INTRO Questions & Observations green film?

My pond is 2 1/2 years old, in the last two or three weeks I have noticed a green film on top of my water. We had a 3" rain last week and it went away for a few days, but it is back. It covers about 1/4 of the water. At first I thought it was duck weed, but it's not. Does anyone have any info on what to do to get rid of the problem?

thanks Mark

This is the only thing I found in my book that might might be what you have in your pond. It is called Plantonic Algae and is listed as toxic algae. The book says to apply 0.6 CLTRINE PLUS per acare-foot per foot acre diluted at least 20 to 1 to achieve uniform dispersion. Several treatments may be required for seasonal control.

Again, I don't know if this is what you have but maybe it's a starting point and maybe one of the experts can tell you what you have. I use Israeli Carp and Koi to control my Filamentous Algae very effectivly. See my web page if you want to try this and to see where to get Israeli's, and to ask them if they would control you particlual algae after you find out what it is for sure.
John

thanks for the info, still not sure if this is what it is. Its not there early in the day, but as the afternoon and evening it appears on the surface.

Mark

What you are describing is the same thing i have been experiencing. From what I can tell the stuff appears in the heat of the day and as you said disappears when it rains. Now here in Southeast Texas we have not gotten as much rain as we would like and as a result this unknown meanace has at times made my pond look like a septic tank.

Not wanting to use any type of chemicals in my pond, I deducted that if rain made this stuff disappear then maybe I could place a sprinkler on my dock and let it work the surface over for me. It aided by my fountain made the stuff disappear! Now I know that this won't work for you guys with five plus acre ponds, but for my 3/4 acre hole in the ground it helps a great deal. Also if you do this maybe once a week for a couple of hours the green stuff will be contained. Hope this helps!

John - a few posts up from this one, you inserted a page from some publication - could you share the source? It's looks like pretty good stuff!
Thanks,
Dave

Dave - that page is from "HOW TO IDENTIFY & CONTROL AQUATIC WEEDS AND ALGAE" (or something along that line); published by Applied Biochemists (the mfgr of CUTRINE PLUS and AQUASHADE).
It is a good reference book for small pond and private lake managers. Cost is approx. $15.00 - I think. Bob Lusk should have them available for sale. If he doesn't, check back with me. KD

Mark- What you have is very likely a planktonic algae, but it may not be the bluegreen algae as referenced earlier in the "weed book". If it is not a bluegreen, then it is rarely toxic.
Only a few bluegreen species are toxic.
Since your pond is fairly new and if you have been feeding your fish, it is very likely your surface film is primarily composed of an bright grass, green, alga called Euglena; this does not belong to the bluegreen alga group.

No one will know for sure until it is looked at under a microscope, otherwise everyone is just guessing.
Euglenoids and numerous bluegreens favor real warm water of summer, however each type has somewhat different water quality requirements. New ponds rarely get bluegreen algae blooms; it is possible but not likely.
If the problem is not severe where it is interfearing with swimming or the algae is pileing up in thick wind-row layers; I see no need to treat, it will dissappear when the water cools and may not return next year.
If you treat, wait until it is all in one corner (from light wind action) and spray JUST the surface film with Cutrine-Plus.
The fish mentioned earlier by John will NOT eat it.
If you need to know exactly what it is, I can identify it; contact me.
BCody