Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants Does this sound right?

Hello All,

I moved in to my current house about a year and a half ago. Last summer, the algae in my pond got BAD. I ended up using a wet-vac to suck up all the muck off the top.

I want to control the algae better this year. I bought a bottle of "Tetra Pond Algae Control" at Menards. I did some calculations, and now I figure I will need FIFTY-ONE more bottles of this stuff to treat my pond once! Oh boy, please help check my calculations.

My pond is oval and about 112' by 85'. I think the deepest part is about 15' and the bottom is shaped like most ponds and lakes, with a gradual rise from the bottom to the shore. I reckon the average depth is about 6 feet. It has a rubber liner. Using online calculators, I figure my pond holds a minimum of 316,000 gallons. Since one bottle of Tetra algae killer treats 6000 gallons, I need 52 bottles. Am I doing this right? What should I be buying instead?

Thanks for reading!

texchevy

Tex-
Welcome to the PB Forum! An important first step is clarifying what you mean by 'algae'. We have actual experts on algae on the forum (see Bill Cody), and the first step toward treatment would be knowing what plant you are trying to treat. Take some pictures. Use a shallow white dish and float the plant/algae in the water and take some focused, clear pictures. Once we know the species, the best/most cost effective treatment can be offered. Also, check out the forum section on 'controlling unwanted plants', and you may find exactly what you are looking for pretty quickly.

Go to this link and id the plant.

https://aquaplant.tamu.edu/

Ok, I'll do that soon. Thanks!

tex

Welcome to the forum!

What part of Wisconsin? I have relatives in Vilas County and went to college in Stevens Point.

Those calculations seem to be correct.

Don't use that stuff, it's too expensive. That is for a small koi pond. If it is algae, you want to treat 1/4 to 1/2 the pond at a time and it all depends on where the algae is growing. If it IS filamentous algae and it's on the surface or in water less than 2' deep use Cutrine Plus Liquid. If it is in water deeper than 2 feet deep use Cutrine Plus granules. If there are Koi or Trout in the pond use a product that does not have chelated copper or any type of copper in it like Green Clean Plus or Phycomycin.

You don't want to treat the whole pond at once because if all the algae dies at once, it could cause an O2 crash and then you could possibly kill any fish that are in there.

Hello!

I don't have pictures, but I went to that website to identify it and it is definitely filamentous algae. Green and just a sloppy mess. What most people call "pond scum".

In my pond I have a great number of perch and a larger fish (about 12-18" long) that I haven't been able to pull out of the water yet. Hopefully there is a treatment that doesn't render the fish inedible. Also, I have an aerator that runs 24/7.

Esshup, I'm in the Green Bay area.

tex

Actually here's a couple of pics.

There isn't much FA in the pond right now and the wind has blown what there is up against the shore.

tex

Sure looks like FA mats. Esshup (of course) is right on the money, with treatment. Lots of threads on FA management in the forum too. Breaking your nutrient wash in cycle is also helpful. I started using biochar granules in erosion socks, wrapped around my intake pipes, to bind up and filter out some of the nitrogen and phosphates coming from Ag fields across the road. Has really helped. I still rake FA out, use pond dye to keep light penetration down, put down granules and spray top mats too.

That website also has treatment methods.

https://aquaplant.tamu.edu/management-options/filamentous-algae/

All of the algaecides that are rated for pond use, providing they are used according to the label, won't affect the fish at all. Now the part about "used according to the label" is the important part. I had a customer that had an algae problem and wanted to purchase enough algaecide to treat the whole pond for a year. I measured the pond and calculated what he'd need for the rest of the year. I told him how to use it and when to use it. He thought he knew better than I did, and didn't want to keep treating his pond every two weeks. So he put ALL of the algaecide in the pond at the same time. "It's enough to last the year, right?" He killed every fish in his pond.

Using anything incorrectly can lead to bad consequences. Take a human drinking water. It's safe right? And we need to do it every day. Did you know that if a human drinks too much water they can die? So, "safe" is a relative term I guess.

esshup has the info correct. Now that a lot of the algae is windrowed up against the shore, I would remove as much as you can then treat the remaining leftovers. This results in using less algaecide. Removing FA removes the nutrients that it absorbed to grow abundantly and then it is not dead / dying /decomposing making muck and releasing nutrients on the pond bottom. The chemical killing the algae in that area is also killing the decomposing bacteria who will hopefully decay the dead stuff. Bacteria has to repopulate first then they can decompose. Firstly remove as much FA as practical then treat. Remember excess nutrient buildup in the pond is what causes the FA to grow.

The linked website includes manual removal as an option. On floating FA it is a preferred method for the reasons esshup and Bill note. Hard work but with good results.

When the experts above say to manually "remove the FA", they mean to remove it entirely from the watershed of the pond!

If you let it decay on the bank of the pond, then those nutrients will go right back into the pond over the course of the next year - and the algae will continue the growth cycle.

I only rake small amounts from my ponds, but our expert rakers have given advice to first get it on the bank. (Preferably some place that your wife will not castigate you for making an eyesore at the pond!) Then let that heavy, water-logged mass of algae dry in the sun to lose a lot of weight. After some period (depending upon your location and weather conditions), you can then scoop it into your available transport and move it out of the area of your property where rainwater runs into your pond.

There is an optimal time to move it. When it is still a tiny bit damp, the mats still stick together (mostly) and are easier to scoop up again. If you let it get too dry and sun-beaten, sometimes it falls apart partially into dust. (It is hard to move dust with a pitchfork!)

Good luck on battling your FA! Even if you are winning the battle for the first year or two, the results might not be easily observable. However, best practices PLUS patience will certainly improve the look of your pond.

FishinRod...
you just about covered every nightmare possible.....my raking days lasted about a day....lol

Wow, thanks for all of the advice guys. I have a lot of work to do.

Speaking of removing it manually, I had pretty good luck with my wet-vac. It's a big one; I put it in the back of my 4 wheeler and with a long attachment, it was quite satisfying watching those big mats of FA go "swoooooosh" lol. I have to dump it a lot, since a lot of water gets sucked up too.

Thanks!

tex

Also, if you let it dry out, and plants grow under it lift it up off the ground it makes a good sun shade for snakes.

Getting the dang FA out of the pond AND creating wildlife habitat!

Proper ID is the key. I was called to a pond today where they were spraying the algae with Cutrine Plus at the proper rate. It wasn't doing anything. I get to the pond and it's half covered in duckweed................

I didn't see ANY FA in the pond though!