Hey everyone. So my pond when completely full has a surface area of around 2.5 acres. 1/2 acre of this is a shallow section with an average depth of only around 9-12" and was included for duck hunting. I anticipated this section of the pond to go dry each year so in my mind I usually omit this area when talking about pond size. This year we seem to continue getting good rains which has had my place completely full since early spring. Right now the filamentous algae has completely covered this shallow section and is now creeping out into the main pond area. My question is, should I be concerned at all with this? The amount of FA coverage in my main 2 acre pond is probably only around 3%. However if you look at this as a 2.5 acre pond, and add in the fact that a full .5 acres is completely covered then that coverage now jumps to over 20%. My biggest concern is a fish kill of some sort if the FA dies, however as of right now, I would imagine my fish load is still fairly low since I only stocked bluegills last year and just stocked my LMB this year. As of right now there is no other submerged aquatic vegetation that I've seen.
If necessary, I can probably just manually remove this with a net since I can walk this portion of the pond with waders however that sounds absolutely miserable in this heat. Next year I will toss in tilapia to control it, it was not advised to put in tilapia this year since my bass fingerlings were just stocked and wouldn't be large enough to help control their population.
With that much FA in the shallow bay the water in the pond should be clear. Correct? What is the water visibility depth? That amount of FA has removed a significant percentage of the nutrients from the pond, thus there should be less phytoplankton and more clear water.
Are you fertilizing the pond???
At this point for the amount of FA,,, IMO I would remove what ever you can physically remove from the main part of the pond without having a heart attack. Texas is a hot place. Maybe just do it a little at a time and in the evening or morning or during windy days. Remove what is practically feasible. Each scoop removed removes some FA bound up nutrients. Do you have a backhoe that you could use for a purchased or fabricate an algae weed rake??? Add a wide screen to a rake like that used in the video that replaces a bucket on a backhoe. https://www.youtube.com/shorts/6aRyrmyDc3A https://www.youtube.com/shorts/1n03a93FbCs
Put a type of screen webbing on this rake and mount it on a tractor or backhoe. Nice Wide rake for adding a webbing screen to remove FA
I would not be concerned with this amount of FA causing a whole pond DO kill since it is basically in the shallow bay part of the main pond. If it all died at once the loss of DO would be mostly in the shallow bay part of the pond. Worst case some fish in the shallow part could die. But many should find their way back out into open water as the main DO loss occurs. However without applying an algaecide (FA killer) rarely does all the FA die at once to cause DO shortages. FA blooms or masses usually naturally die gradually over week long periods and as the DO decreases I think most of the fish in that low DO region will seek deeper water of the open water 2 acres where DO is high especially if that water is clear with good normal density of clear water phytoplankton for DO production. The other good thing for your new pond situation is all the fish are still smaller and able to better tolerate periods of low DO at least for shorter periods such as 8 to 16 hours.
Keep an eye on it and keep us updated..
Last edited by Bill Cody; 07/15/2607:58 PM.
aka Pond Doctor & Dr. Perca Read Pond Boss Magazine - America's Journal of Pond Management
CentexSaj, I'm scratching my head trying to grasp the advice given to you to not stock tilapia this year, as the LMB wouldn't be able to control their numbers? It seems to me that you certainly do Not want to limit the tilapia population if FA control is the goal, right? The more tiny TP eating the FA, the better. I don't suppose you'd expect TP to over winter in your pond, do you? Can someone clear this up for me?
So my water clarity I think is around 18" currently. Last year it was only around 12" (I need to take a measurement next time I'm out). I was able to plant a lot of rye grass on the banks over the winter which I think really helped stabilize the banks to help with the clarity. The water is stained brown and I have done a jug test where alum cleared the water up pretty quickly. So, I definitely have some suspended clay particles which I'm fairly sure is affecting the visibility, not a plankton bloom. I have decided to not mess with the water clarity until I can get vegetation grown on the banks which has been a lot more difficult than I thought. (droughts suck for growing bank vegetation)
I'm not fertilizing the pond, however this year however the biomass of flooded grasses and what not was much greater when the pond filled back up to the top compared to when it initially filled. So my assumption was that was likely fueling the FA growth this year.
As for adding the tilapia, the advice was likely given a little bit more based on my situation at the time. There was very minimal FA growth at all, my shallow end didn't even have water when I posted the question, and the number one reason that I actually wanted them was to have some other fish in the lake for the cormorants to go after so they would lay off the bluegills/bass to give me a chance to put up some protection measures once they arrived. I also went with a different company to do my stocking and they were bringing a truck from a fishery that didn't have tilapia, otherwise I probably would have still thrown in a few.
We do have a local place that sometimes has tilapia, I guess I could call them up and see if they still have some.
I went back out this weekend and measured my clarity level. Looks like I have around 26-28" in the middle of the pond. Definitely more of a green tint to my brown water which I am taking as a good sign. The clarity definitely changes depending on which bank you choose. Crazy is that with the little bit of wind we had, it was able to uncover half of my shallow section by blowing the FA up against the shore and just compressing it, I guess.
