Pond Boss Forums GENERAL QUESTIONS Water chemistry Algae?? And now comes the FISH KILL....

Over the last week or so my pond is starting to develop a heavy algae bloom. But it is something I don't think I have ever seen before.

The first 2 pics were taking yesterday and the last one about an hour ago.

Is this normal?

Holy moly...that is a bloom! Does that plankton in the third pic look blue-ish? I am no algae expert, not even a novice, but surely hope it's not toxic blue-green algae. Need some help from the forum experts.

I'm right there with ya schmidt...my big pond is probably 40% covered, and 90% of the growth has happened in the last week or so. I'm in the middle of devising a scoop to mount on the front of the pontoon boat to see about removing a bunch of it.

It apperas that the thick stuff is wind driven to the downwind side of the pond. Is that correct?

It is a plankton bloom and dense. What is the visibility of the water in the upwind portion of the pond?

In the 3rd pic there are blue chunks floating in the mix of it all. From what I have read blue-green algae will not clump together, but I may be mistaken.

That skoop idea might not be a bad plan...

ewest, you are correct. It is concentrated on the downwind side of the pond. The upwind side had a visibilty of at least a foot or so last night, which is GREAT for my pond.

I would keep an eye on visibility. You can easily break up the thick areas with a little water movement.

Anything I need to worry about? Should I try to get what I can out of the water?

The algae is feeding on the nutrients in the pond. Once it dies and decays, the nutrients are recycled. By raking out the algae and getting it out of the pond basin, you'll be removing the nutrients from the pond, helping to break the cycle of bloom, die, decay. As it decays it uses O2.

IMO it is always a preferred option to manually remove unwanted plants for just the reason esshup mentions. Often it is not practical due to the effort required. It can be next to impossible to remove plankton. Often but not always the plankton you see on top and wind driven like you pictured is soon to be dead. It can't hurt to scoop it out and put it on the bank. I am talking about phyto/zooplankton not thick blue/green algae (cyanobacteria). I would scoop that out if possible without a lot of effort.

Do you think that this is cyanobacteria? Or just plankton? Is there any way to tell without sending off a sample? Thanks!

My guess is you have some of both. Looks like mostly planktonic with some bluegreens (cyano). Bill could give a much better guess.

Bright bluegreen patches are dying bluegreens - a common symptom of some of the decaying Cyanobacteria. My guess is a lot of the other film is also Cyanobacteria.

That's lovely! Is there anything I can do about it? How harmful is this stuff? I know the department of health around here makes it sound like a serious plague. My cats have been drinking out of it during this time and they haven't keeled over yet.

I have about 40-50 fish in traps right now, should I clean them now, wait till the bloom is gone, or just trash them?

Also, what are some ways to prevent it in the future?

Thanks for all the help, not sure what I would be doing without the help of POND BOSS!

How is your visibility now? If it stays the same or gets better (greater than 12 in) I would just keep an eye on things. If you have a boat you could go out with a paddle and break it up (much will disperse and sink). Any type of water movement would help. I don't view what you have as a serious problem as long as the visibility is 12 in or more and getting better (18 to 24 is better).

Do you know your alkalinity?

My visibility is still around the 10" - 12" mark. That is the best it has ever been since I purchased the property back in February. I do have a 3 person pontoon I can get out there with and stir some things up.

I can check the alkalinity tonight after work and get back to you on that.

I would not be overly concerned about any toxic effects from this algae. Even if it is cyanobacteria, only a few specie emit toxins. You would have already noticed any harmful effects i.e. dead fish (or in your case dead cats). Remediate as with any other algae bloom.

Wind picked up today and the bloom is mostly gone. A lot of green flake looking pieces suspended in the water now though. Did a water test and came up with the below:

Total hardness: 100
PH: 8.4
Total alkalinity: 120
Cyanuric acid: 100
Chlorine and bromine all 0's

That water looks good to me. Keep an eye on things an as long as the visibility is increasing you should be ok.

So what if the visibility goes south? Got home today and the wind blown side still has a film and some built up algae on it. Rest of pond surface is clear but visibility is down to about 3" and looks pretty green.

I read back through this thread and could find no mention of possible run-off. What has been the rainfall situation at your location? Is any on the land adjacent to or near the pond used for agriculture or livestock. This could be the source of your evident high nutrient load. In order to find out how high, you will need to test for Nitrate and Phosphorus. How much aquatic vegetative coverage do you have?

This pond is in my back yard. We don't use anything on our lawn and do not have any ag land up to it. I also have no aquatic vegetation in the pond. I am assuming that this is the negative result from using alfalfa bales to clear the water as my neighbors pond has 0 visibility but no algae problems. The two ponds are separated by about 20' or so.

And for the rainfall... What is that like? Predicting worst draught since the dust bowl in 1930 for our area...

Organics decaying add nutrients to the water. Either FA, Phytoplankton or vascular plants will utilize the nutrients. You might want to aerate if you are not doing so now, because if the Phytoplankton has a sudden die off, O2 will crash and fish will die. All that algae will cause O2 levels to get low by first light too....

Lower water levels are concentrating the nutrients into smaller volumes of water too.

Without vegetation to use up the nutrients, you WILL have algae.
I thought that you were in drought conditions, but wanted to be sure. Really a bad situation, 61% of the lower 48 in some level of drought.

I don't have an aeration setup nor know where to even begin with that process. Everything I have read on that sounds pretty expensive to get setup properly.

Will there be any sings leading up to a fish kill or will it happen all at once? For instance, will fish stop coming to feed, start looking unhealthy, etc?

What type of vegatation would help limit algae in the future? This drought is crazy, I thought we were better off than last year but it doesn't sound that way. I think there will be a well project in my future before next spring.

When you notice signs it's probably too late.. Fish will be piping at the surface trying to get air.. You will either notice real little fish around your edges or as in my case all the big fish died first because they need air the most.. No problems since aeration..

Any chance you can move the surface water around by motor , pump etc ?

That's what I figured, just wanted to cover my bases in case there was something I didn't know about.

I can't think of anything off the top of my head to get the water moving, besides getting out in the pontoon and paddeling around. However, the south side is now just over a foot deep and I wouldn't be able to get in there very well. And I think I'm too shallow to get the trolling motor going through most of it as well. Should I try that this evening, just to stir it up?

The forecast doesn't show anything that should kill off the algae quickly so I am hoping the fish will make it. Being the first summer owning this place, I really don't know what to expect.

What about removing fish from the pond to allow more oxygen for others in case I do start having a low oxygen problem? Would this be a viable theory?

The problem with that theory, as I see it, is determining the number of fish to be removed. You would need to know the present level of Dissolved Oxygen and be able to monitor the DO to determine how fast it is dropping. It also depends on species of fish extant in the pond present day, as tolerance to low DO levels varies with species. Aeration is your only real immediate solution with additional plantings placed for long term stability.

I see and I don't have anything to properly monitor DO. I need to get better about removing some unwanted species (BH) and was looking for a nother piece of motivation. :-)

Unfortunately, if you do have a fish kill, there's a good possibility that the BH will survive. It seems like all the good fish go first.

Well, as the title now reads, I have my first fish kill... So frustrating!

Thought all was well yesterday, green tint was gone and clarity was starting to come back. Woke up this morning to 100's of dead fish floating and on bank. A lot of them are actaully sinking so who knows the real severity. Started with WCP and BG now hit LMB and CC. And thousands of smaller fish near the surface trying to get air.

Tried to rig up an air pump and hose with holes drilled in for aeration but I'm not covering much area with it and it's all I have right now.

Guess I will be adding an aeration system on the list of "to dos"... SOB!!!

Tragic news! Major clean up! Be sure to place the aerator at the top of your 'to-do' list...right after 'add plants'.

Doubt it makes you feel better but worst year for fishkills in a longtime. THis heat has been brutual to many pondowners. I wish I saw this post earlier I woudl have advised you to mist with copper to slowly kill the phytoplankton. It has saved fish on many ponds this year. Slowly kills it back before a severe crash. I think you had a crash so thick sunluight blockeed to other plankton. The reason you saw it turn colors was dying phytoplankton Im afraid.

We have alot of water flowing through our hatchery ponds. We treated vegetation agressively thinking with inflow no biggie. Matt noticed fish piping so put in emergency aeration oxygen was 0.89. It saved most but lost the grass carp. Point being we know what we are doing and still bout screwed up. It was cool to see how quick a surface aerator works to correct. Small pond but went to over 3 ppm in less than two hours. Over 6 DO in less than 5 hours.

Man with hot water there just isn't much oxygen holding capacity of the water. Doesn't take much to get in trouble.

Especially with cold water species of fish.

So what all do I need to do to make sure this NEVER happens again? I've been looking at RC51's aeration setup. Is that a good start? Would surface aerator be better in the long run instead? How much vegetation should I put in? How long does a fish kill usually last? What are the odds of survival for different species?

Do you guys think the little air pump and hose is doing any good at this point or is it a lost cause and I just need to start putting more concentration on how to prevent this in the future?

I just came back in from picking up more fish... More CC, LMB, BG, HBG, BH and even more WCP.

Of course but you can get in trouble with coolwater and even warm water fish with the right conditions.

Schmidt's - Sorry to read about your fish kill. Been there done that!! I know it totally sucks. Large rum and diet cokes all day long while scooping up large BG, LMB,and WE after a winter freeze out.

Good luck on the next go around.

Sp sorry to hear about your kill! I'm afraid it's not going to be the last one reported this year from the pb family. What size is your bow? Have you considered starting over since you have bh and wcp?

Yeah, it's been a long day! The thought of starting over may be a possibility. I think before we get to fall and possibility some rain I will seine it to see what is left. My pond is about 1.5 acres at full pool and 6'-8' deep. However, right now it is just under an acre and 3'-4'.

I know it's hard to stay positive right now but after my first fish kill I learned soooo much and met some great contacts that helped me out. I would bet a fair share of money if you really love pond management your fishery will be far better this time.

If you know that your fish are lost, this is a great opportunity to do any in water projects such as adding a swim beach or deeping a section. I did both before restocking.

I'd plan on starting over. With that shallow of water, it'd be a great time to drain and make it deeper. I'd cut my losses, forget about the aeration system that you've got going and do some planning.

At 6'-8' deep, I think you really aren't deep enough for your winters. While an aeration system might prevent most winterkill, if it's a long, cold winter, that shallow of a pond will get pretty chilly for the fish.

Someone local just lost two labs to blue green alge. Not sure if this is the same or not. It was in Salamonie Reservoir.

I had some blue-green algae but not a lot. Had dogs and cats drinking from the pond every day and they never got sick.

If I decide to start over, where do I start? Does anyone know someone in the Kansas area that does good pond work and could make it deeper for me? I reached out to Mike Otto from another post I read.

How long does this usually last?? I spent most of the day picking up fish yesterday and guess what I get to do all evening after work... more fish and they are already starting to stink. Anywhere close to the pond just smells horrible!

Is there anything I can do to stop this from hapenning? Or will it just continue till everything is dead? There are millions of minnows swimming at the top of the water, now even the BH are coming for air!

Here's a quick picture I just took, most the dead fish are windblown to the other side of the pond, may have to zoom in to see all the fish at the surface and the minnows at the bottom of the picture...

If you can get something in there to agitate the surface of the water, something like


Anything that will agitate the water surface will help. Even a trolling motor with part of the blades out of the water running on the highest setting. Just make sure that enough of the motor is in the water to keep it cool.

It'll help a lot. If not, then the fish will keep dying until there is enough O2 in the water to support the fish that are left. If there's decomposing organic matter in the pond, then there's the possibility of all the fish going belly up.

Silver lining is that this will allow you to start with a clean slate. You could renovate the pond, making it deeper and not worry about killing any fish in the process.

This is my fish kill insurance policy:

I did do something like that with an air pump all day Sunday and Monday. I shut it down when I saw BH at the surface gasping for air and pretty much every other fish in the water dead. If everything is going to die, then those pain in the --- fish need to die too.

I do have thousands of minnows still swimming around the shallows at the top of the water. No idea what species they are, but I do know there are several different species mixed in together.

Talked to my neighbor who has lived there 20+ years and he has never seen a winter or summer fish kill in his or my pond. The water was even lower last year he said. That determines that I in fact caused this by adding in the alfalfa and increasing the nutrients to the pond. With that being said, I don't think I can justify going deeper with never having a problem over the last 20+ years. I think our plan will be to install an rc51 system and a well to help keep it closer to full pool.

Today at lunch I did not see any fish gasping for air and we do have 25+mph winds today. Fish kill may be over? Good news is 90% of the fish I picked up were all crappie, guessing over 600. All about the same size and bug eyed. If I can continue to pull out more bh i may get a nicer pond out of it. Fingers crossed and wife willing!

It is possible that you were to near carrying capacity with all those crappie. That greatly increases the chance of problems including DO crashes. My guess is that you did not cause the event with hay but may have added a little to the problem. Moving the water will help !

I was actually wondering that myself. 700+ Crappie dead worried me a bit. As for the rest of the dead I picked up, <30 CC, <20 LMB, <100 GSF, <20 BG, PS, RES, HBG.

Nothing new floating yesterday so I threw the traps back out to see what's left. Caught some GSF, BH and the attached. I would like some help with the ID but it looks like a WCP to me, about 2" long.

If it is in fact a WCP, is it safe to assume that not all CC died either? I tried throwing out some feed last night and had nothing come to it besides turtles.

I think you ID'd it correctly, and I think your assumption could be correct also.

That is a crappie and looks stunted with the large eye. You have what most fear when stocking crappie, I can now see where they can be an issue.

I put them in my small pond as well not knowing any better. I did stock Black Crappie which ended up being the black nose crappie, but I think even though they do not spawn as heavily as the White Crappie (or at least this is what I was told) I can still have issues.

Did you have any larger crappie that were dead?

Do you have a picture of the trap you are using?

That would be nice if I still had some CC in there. Hopefully I will see some at feed tonight.

Every crappie I picked up that was dead was in between 6-7" and bug eyed. I have not caught a single one by pole yet either. I did not stock the crappie, they were here when I bought the place and as you can see, a BIG problem.

I don't have s picture of my trap but I have attached the instructions I found and it shows the complete trap at the end.

What plants do you recommend putting in my pond?

BH Trap Plans will not open for me. Others?

I can't find it either.

They opened for me. It's the link in post #300838

Would not open for me either.

Don't work on IPhone ??

I'm using my desktop, and had to open up a few windows to get to the final instructions, one was a zip file.

I couldn't open the zip file.

I am so sorry to hear about your kill. I have a thread ( 301315 ) very much like yours only without the kill....so far. That is what worries me. Your pond is very green, I do see that.

I was also unable to open up the zip, I will follow the link that esshup listed and see if I can have a look. I also need to get some fish traps, can I ask you where you got them from?

I don't think I saw it mentioned, but did the kill follow a couple of cloudy days? What are you doing with all the fish, it must be very difficult to get that many fish far enough away from your house? I know it must be such a blow to try so hard to get it right only to have the fish die, and I wish I could offer you more than my sincere condolences, I fear I am on the verge of the same problem as you are having and I am at a loss, but I am getting some great advice if you want to go have a look. I hope you can find a solution to this.

I found where it was on the 'net.

Bream (BG) /Bullhead trap

Sorry about that guys. I had to zip it in order to upload it. Looks like you have a good link going now.

Someone mentioned on here to get some plants in the water to help absorb the nutrients. Any recommendations on what plants to get in my pond? Right now there is 0 vegetation in the water. Thanks.

Is there such a product as a "quickie" aeration kit? Something you can buy at a local store, plug into an outlet and turn on, right now, to at least aerate a limited area?

Yes - it is called a fountain. Paddle wheel aerators are a good option. Might be able to rent one from a fish farm.?? The more splashing and horespower the better. The big problem is, the fish have to be smart enough to go to the noise and activity instead of avoiding it.

I'll start looking online. Got any recommendations for a specific product? My new, half-acre pond went from sweet and clear to a dark, roiling green literally in 24 hours. I'm stunned.