Help Me I've been slimed

[Marty]

I need some help and advice on my pond problem. My pond is getting neon green slime on the top every afternoon for the past three days. I go out with a bucket and skim the layer off and throw it out of the pond. I will give you info that might help and need advice to save my pond.

It is about 5000 gallons 8'x32'x 3 feet at the deepest. Running for 3 years with the same hardware

Live in Tennessee we had some pretty humid days the past three days but before that it was really dry and sunny for 30 days.

I have sun shades that coves 75% of the pond to keep algae down
I use about one inch of the water each day to water my garden and replace it with aerated tab water.

I have a 3 layer waterfalls with charcoal section and a DIY filter system made of polyfill and sponges and ac filters

I have a 820 gph pump going 24 /7 to a 38watt uv filter grabbing water 10 ft down from the waterfalls at a depth of 18 inches and putting the water into the water falls

I have a 1.5 hp spa pump that runs every 2 hours for ½ hour during the day 8am to 8 pm. That grabs water from the far end of the pond in a 1.5 inch pipe and goes the 32 feet at a depth of 2 feet down.

I don’t know the gph but it really puts it out and makes a lot of bubbles and turns the water over the falls pretty good.

Have about 90 goldfish and kio (small sizes most are 4-5 inches have one big guy about 12 inches). Also have 3 water lily and a water bamboo that I keep in the waterfalls area.

I put that blue stuff in the water to reduce algae yesterday hoping that would work. Pond temperate is about 70 degrees. I feed them once a day only what they can eat .

Any help I would love. Here are a few pictures that might help

Thanks Marty

Fish eating after cleaning above
Waterfalls below

Sun Shades below

Slim in bucket after scooping out

Slim in Pond floating

 

[Big Lou]

Welcome Marty. Lovely pond, falls and koi. Your pump may be too small your pond. Let's see what the experts have to say.

 

[Lisak1]

Well, it is a lovely green color, isn't it?

Clarify for us - do you only run your pump for a few hours a day? You should aim to turn your water over every hour at the least - so you should be running at least a 5000 gph pump 24/7. I'm going to suggest a combination of too many fish, too little water turn over and too few plants for the bio load.

Let's see if anyone agrees with me!

 

[MitchM]

Marty, is there any smell to this slime?
I'm wondering if it's cyanobacteria, which is not an algae.
Also, have you performed any water tests such as PH, temperature, phosphate, nitrate, or anything else?

Lou is right, your water flow amount sounds low.

edit - Lisak also makes some good points.

 

[Marty]

thank you for your responses
to clarify the smaller pump runs 24/7 and the spa pump runs 6 times a day for 1/2 hr. for a total of 3 hrs.
it smells a little fishy but not horrible
the green slime is only one tenth of an inch on the surface
the temp is 70 didn't do any test
the same setup for three years and this is the first time this green slime has appeared
should i get some sort of skimmer like in a pool?
once i have skimmed the surface the water underneath is very clear,then the next day the slime comes back. i don't want to lose any of my fish.
i haven't had any problems since i set this pond up.

 

[MitchM]

I suspect that it is Cyanobacteria.
If you have any pets, do not let them drink from the pond, Cyanobacteria can release toxins that are poisonous to pets.

Warm, slow moving water that is high in nutrients are the conditions that Cyanobacteria lives in. In order to get rid of it, you need to significantly increase your water circulation and filtration. A pond your size should have 5,000 - 10,000 gph 24/7 circulation with appropriate filtration. Whatever you have now is not enough.
There are various treatments available to get rid of the bacteria, but the first step is to clean the water and any detritus that has built up.
One treatment involves the use of an antibiotic, erythromycin, but that should only be used as a last resort as it will also kill the beneficial bacteria population.
I prefer other treatments that oxidize the bacteria, but you really need to provide aeration and strong water circulation during the treatment.
Check with your local pond store to see what they carry to treat Cyanobacteria.

 

[MitchM]

For more specific information, Google Cyanobacteria or blue- green algae.
Check that the images on-line match what you see on your pond.

 

[Tula]

I agree , it looks like cyanobacteria or blue- green algae. I was just reading an article about it the other day in a dog magazine and it looks very much like the pictures. The article, discussed the danger it poses to pets that drink it...it can be fatal.

 

[Marty]

i was just on line trying to learn more about the blue green algae,one of the responses to remove it was putting barley straw in a fishnet sack and submerse it for 8 weeks and then remove it has anyone else heard of this?

 

[MitchM]

I haven't seen anything definitive on that, but bottom line is that you need less nutrients in your pond, not more.

 

[addy1]

After years of running the debris may have finally accumulated to the point it is causing this algae bloom.

Yes I agree with the above, you need to run a bigger pump 24/7 also maybe add a good aerator in the pond. In your waterfall pools put some plants to help remove some of the nutrients.

I have no shade on my pond, do have a pump that is rated for 6800 gph runs 24/7 and a aerator. Never have seen that type of algae on my pond.

Test your water for nitrites, nitrates and phosphorus. The test kits are around 20-30 dollars, liquid test kit.

 

[Lisak1]

The main message is you need to increase your water flow and the sooner the better. Also, I wonder if you may be doing more harm than good by running the pumps for a limited amount of time. It may be better to keep them off all together. This may be just a weird theory, but when we turned our pump off for the winter, the first water out of the bog in spring was smelly smelly smelly. Completely anaerobic. It's one of the reasons we decided to run our pump all winter long. I wonder if it's possible that turning your pumps off is creating a similar situation in your pond repeatedly?

Someone with more knowledge than me may say I'm completely off here, but I know ponders with goldfish ponds that run no filter, pump, waterfall or aeration at all who don't have water quality issues.

 

[johan]

When was the last time you changed your UV bulb? They do lose effectiveness after about a year, I'd start with that. More flow will make a difference, but also adding aeration to promote gas exchange

 

[Marty]

I changed the UV light and upgraded to the higher wattage bulb last month when I did my spring maintenance
I added a Skimmer used my old 680 gph pump to work that and added a new 6000 gph pump for the waterfalls 24/7
I cleaned the bottom of the pond yesterday It was really loaded with leaf debris.
Hopefully this will cure it
Thanks for all your info people I appreciate it
I will let you know at the end of the week how it is

 

[MitchM]

I am interested to hear how it turns out.
Depending on the strain, cyanobacteria can also coat surfaces under the surface, so keep an eye out for that.
It can be tough to get rid of without using a chemical treatment.