When the water is not just green, but you actually can’t see through the water, almost like pea soup, what you are seeing is a type of suspended algae called microbial algae. This type of algae is actually microscopic plants! This can occur when the pond ecosystem is not in good balance. Nature found a way to consume the nutrients in the water that weren’t being utilized. Now you have green water!
The pond above has microbial algae, although it could be worse. You can see somewhat down into the water.
Suspended Pond Algae and Dust
Sometimes the suspended algae is so dense that it will settle on rocks. When it is brushed away it just clouds up as if it some dust, clouding up the water more.
Green Cloudy Pond Water - What is really the Culprit?
How much are you feeding the fish?
Uneaten fish food is like dosing the pond with suspended algae!
When you feed the fish, give them what sure they can eat in about 3 minutes. You need to stand there and watch them eat. Watch to see if food is being swept up in the current and taken to the skimmer. The food gets mushy after a bit and the contents just melt into the pond water. This nutrients overloads the pond system creating the perfect opportunity for suspended algae to get in there and wreak havoc!
When I really want to check and see if the fish are being over fed, I put a fine net right in front of the skimmer and then feed the fish. After about 10 minutes I check the net. If there is food in the net then they are being fed too much!
Suspended (or microbial algae) doesn’t really hurt the fish. Although, it has got to make it harder for them to see!
Will Changing all the Water Out Get Rid of green water?
It is so tempting to just take all the water out and put in new water in the hopes that it will get rid of the green pond water. Unfortunately, it will just come right back!
But WHY? Because the conditions that caused the algae are still existing. The ecosystem needs to be brought into balance as a whole.
The reason that it may still be a good idea to remove the water is so that debris and muck can be removed that may be contributing to the problem.
Cloudy Green Water Check List
►Check F.R.O.G.S.S, the basis for a healthy pond.
►Do you have a yard service who is Applying fertilizer near the pond? Does the land drain down into the pond? If so – this can be a major problem. One mistake people make is building a pond at the lowest point of the yard. Dealing with who knows what running off destroying the balance of the ecosystem.
► Are there lawn clipping when mowing getting thrown into the pond? This excess organic material will definitely cause algae.
► Could there be low oxygen? A pond pump should be able to circulate all the pond water each hour. The water flowing over the stream and waterfalls oxygenate the water. Additional aerators help too, especially in spots where there is less circulation.
► Are you using algaecide? Are you using Algaecide and bacteria at the same time? If you use algaecide it might clear it up but it will come back again without regular treatments. And worse yet, it kills the beneficial bacteria that is a part of keeping the ecosystem healthy.
► If the pond full a cobble? 4″ and larger cobble stone in the bottom of the pond without 3/4″ gravel is almost the same as putting in algae seeds. This size round gravel gives just the right spaces for beneficial bacteria to colonize and keep algae down.
This suspended algae is thick and even looks dusty.
Patience - The Key to Getting Rid of Cloudy Green Pond Water
Patience alone won’t do it. However, using patience along with some water treatments and ecosystem balancing, you can get your water clear again. If NOT using algaecide do this:
♥ Make sure you have corrected any items on the green Water check List.
♥ Add a 1 1/2 doses of bacteria weekly (depends on the size of your pond check the Gallons Calculator if you aren’t sure) while you are trying to get the green cloudy water under control.
♥ I like to add a pond gummy. It is very concreted bacteria.
♥ Use Flocculant. It binds organic material (like suspended algae) so it can more easily be caught in a filter.
♥ Put in a fine white filter pad inside the skimmer net or basket and remove it to rinse with the hose every hour – 2 hours or when ever it clogs for a day. I know. It does seem like a lot of work, but it will help. Don’t leave a fine filter pad unattended for long, it can clog.
♥ Be patient. It will clear up when the system gets in balance.
What About Algaecide to Getting Rid of Cloudy Green Pond Water
The above ways of getting rid of it are part of balancing the eco system.
I am wary of algaecide because it may harm aquatic plants and although many say they are safe with fish, may kill the fish if not used precisely. The first dose is from 1 to 2 ounces per 1000 gallons so it doesn’t take much!
That being said, in a system that does not have the elements of an ecosystem or fish, Microbe-Lift AlgAway 60 will kill the cloudy green algae. Seriously – I almost didn’t write this because if this is not used correctly it can kill things you don’t want to kill!
I did look directly on their website and it says it will not harm fish or plants. It registered with the EPA, so I would use it with caution. Remember, that when you use algaecide it does kill off the ecosystem. It is sort of a choice. Do you want to have a lush ecosystem that supports the local environment or do you want to kill it to get rid of the green water quickly?
Have other algae issues? Wondering what kind of algae it is? Does your feature have BLACK algae? Don’t have microbial algae, but have something else? Read about types of algae to figure out what you have.
* This blog was NOT written by AI. This was written by me. I am not a professional writer, I am a pond person. Therefore, if you see a typo, please forgive me!
*No koi were harmed in the making of this content.