Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Using algaecides ??

Still having FA issues in my pond. Stocked 10 grass carp in November and 10 more yesterday. Someone suggested spraying K-Tea on surface when wind has blown FA into one corner of the pond.

Also suggested putting a pound of copper sulfate in a cheese cloth and tying to a piece of styrofoam and throwing in the pond so that it will float around the pond.

Have been reading about copper sulfate and K-Tea and some said that using copper sulfate can be bad for the pond and will eventually accumulate in the soil and kill microscopic snails, etc. Recomended using cutrine plus or ultra.

I am hoping that the grass carp will get the FA under control eventually and I will not have to use any chemicals. Anyone have any thoughts about spraying K-Tea on the surface accumulations or the copper sulfate in cheesecloth idea or alternatively using the cutrine?

Thanks

Hey Boat if your talking about the floating nasty snot looking FA on the top of your water Grass Carp wont mess with that... they will however eat chara which is another from of FA but looks and feels more like a plant. I have used cutrine plus granular and like it. It's a bit pricey but does the job I think. If you can have them some folks use Tilapia to control FA, but you have to make sure you can have them in your area.... Grass Carp will not control floating FA.... Sorry

RC

I've had very good results on FA with Cutrine Plus Granules.

Before Cutrine Plus Granules:



After Cutrine Plus Granules:

Cutrine Plus has worked well for me also, but be very cautious to not treat too much at one time! There's much on the forum about an O2 crash when treating too big of an area.

I've used liquid for the floating mats, granuels for submerged.

Treating too much biomass of algae (or submerged plants) at one time, with any product, is of greater concern than the size or percentage of area that is treated, since it is the decomposing plant or algae biomass (actually, the oxygen-consuming microbes which break down the dead biomass) that increases the pond's biological oxygen demand (BOD) and potentially leads to inadequate oxygen-levels for the survival of fish.
Just wanted to clarify that second sentence, since treating a large biomass of submerged plants or algae - even if they occupy only a relatively small portion of a pond - may lead to DO issues under certain conditions, especially as water-temperatures increase.

I've thought about using Cutrine or some other Algecide on FA but I'm concerned about what it would do to my fish, or what that means for us eating fish out of a pond that's been treated with chemicals. How long has this product been around? Has it been thoroughly tested?

For Filamentous Algae, if you are worried about eating fish out of a pond treated with chemicals, I would stock a minimum of 40 pounds of Tilapia per surface acre within the next week or so. That should allow you to not have to teat the pond with any chemicals for algae control, provided you don't have a 15%-20% or more surface coverage of algae now.

For myself? I use both chemical and biological controls in my personal pond. I apply chemicals where needed according to the label, and have no qualms about eating fish out of my pond.

I figure that with all the testing and regulations that are in place, I have more serious things to worry about as long as I read the label completely and follow the directions.

Thanks Essuph, I have a 1/2 ac pond. Stocked it last year (Apr 2015) with 8 lbs of moz tilapia, it was my first year with the pond so didn't have anything to compare too, but the FA covered about 15% surface through the summer. This April I stocked 20lbs of same 3-6" TP,. currently have about 5% surface coverage. I'm starting to see more FA float to the surface. I'm hoping the TP will control it. If not I may consider the chemicals.

Boatman,

FWIW as I live in Illinois, Tilapia is not an option for me to control FA. The only critter I know of that is legal for me to stock to control FA is crawfish. My understanding is that they also eat FA so I'm stocking some in June. Hope it works as crawfish can establish a population and won't require restocking every year.

It takes lots of crayfish per acre to control FA that is abundant enough that it obviously needs controlled. Density of adults and juveniles (YOY) IMO would need to be at least 5000/ac. One crayfish can only eat a small amount of algae per day.

I'm surprised that is all the craws it would take. That's like 1 craw every 8 to 9 square feet. I might have this wrong. Is 5000 what it would take to control the water shallow enough in a 1 acre to support FA growth; maybe a third acre? That would bring the number down to 1 craw every 2 or 3 square feet. Sounds like craws will not provide much control unless you have great cover for them. Unfortunately, for folks like me, in states where Tilapia apparently live year round, even under the ice, I know of no other biological control of FA. Anybody else know of one?

BillD good point. My wild guess estimate assumed the algae was only growing out from shore 6-12ft in an acre pond which is up to 10,000 sqft of algae growth around the pond. This equates to around 1 crayfish per 1-2 sqft of algae growth. This may be a better way to express how many crayfish that are needed to control algae. Expect water clarity to become around 12"-18" with this amount of bottom feeding activity from crayfish. The decreasing water clarity will also reduce light penetration which will slow FA growth on the bottom areas.

Those are good results. My FA has been terrible this year. I failed to replenish the pond dye early enough I think. My pond looked about like your top picture so I sprayed the mats around the edge with Cutrine Plus doing 1/2 of the pond at a time. Did great, so I waited 2 weeks and spread Cutrine granules in 1/2 the pond in water 3 feet and deeper. Did the last half 10 days later. Two weeks later and the mats are coming back as heavy as before. I'm not sure if the granules didn't kill the FA deep or what. I did put the pond dye in when I spread the granules in the first half so it hopefully won't grow much now.

Most people are generally not equipped for large algae treatments. I see guys treat 1 acre ponds choked with FA with small 10 gallon Fimco's or Solo backpacks. Granulars can help by transporting the product to the algae on the bottom but floating algae not so well. I have seen Tilapia work but not in all cases. It's good to try Tilapia and see if it helps.

Getting proper mixing is very important. The general rule of thumb is to mix one gallon of product to 9 gallons of water with appropriate surfactant. This allows the product to move easier in the water column. Starting early in the spring on the pond is crucial to keeping the biomass down to a minimum. In ponds that get the tough algae species like Hydrodictyon and Pithophora you need to be on your game. Keep your pond dyed all summer. My applicators usually chose black dye but most of my clients refuse to let their ponds look like the Masters so we stick with blue. Just sprinkling some algaecide on the top of a large mass of algae will more than likely kill or burn the top layer. The undermass will likely resurface soon after treatment(Remember 9 to 1). Boat wake will also help break apart the mats to allow for a better treatment. If the algae takes over most of your pond just treat in weekly sections until you get caught up. Also don't be afraid to try other products on the market. We use beneficial pond bacterias on our smaller ponds which has proven successful in most cases.