Dear Pond Boss Members,

PLEASE HELP!! I am a new pond owner and dealing with our first summer maintaining the pond. The pond is .55 acre oval shape with 3 aerators and has been covered with a gray / green algae film since July. I have been trying many algaecides, beneficial bacteria, and pond dyes with no success. A heavy rainfall will clear it up for a day and then it immediately comes back within a day.

I first started with Algae Defense and Treatment Booster Plus on 7/26 on 1/3 of the pond. I noticed a small improvement for a couple days but the algae came completely back within a few days. The following week I tried Curtrine Plus. Again small results for a couple days and then back to total algae coverage. Following week I tried Sepro Pak 27 (no improvement). With no progress I had my water tested to see what was out of balance and causing the issues. The main issues are high phosphorous levels and water hardness. I purchased Sepro Phoslock to help with the Phosphorus but everything I've read has suggested to deal with the algae first. So a couple weeks after that I applied Sepro Captain XTR (no improvements) to half the pond. This past weekend I applied another gallon of Captain XTR to half the pond and it cleared up for 1 day (first picture), and then was back to the same problem (second picture) I have also been using Airmax PondClear, EcoBoost, MuckAway, and Pond Dye Plus in between algaecide treatments every 2 weeks in hopes this would help but no noticeable improvement. Please if there are any suggestions anyone has I'd greatly appreciate it!!

Need better pictures. With the photos so far away it even looks like water meal. Maybe some closeups in white background.

Mike

Figure out where the Phosphorus is coming from, then stop that, if you can, so you deal only with what's in your pond.
This is what the algae is thriving on.
You mentioned your hardness is high. How high?
High hardness is known to reduce the effect of copper based algicides (all the stuff you tried).
Reducing the nutrient load the way you are, will help, but will take time.

Getting hit with heavy rains today, but will take better pics again tomorrow once it returns. Pretty sure it's algae because it's bubbling green at spots. It starts out as clear film after rainfall, then turns to gray, then bright green as temps rise and if little wind. I've attached pond results, hardness is 174 mg/L. Had a fish kill the weekend we moved in last year before I could get aerators in and do get lots of large sycamore leaves so thinking that could be source of phosphorus. I don't treat my property at all and don't believe my neighbors do either. Thanks Journeyman and Mfitzs70!

Your surface scums look just like mine and acts the same way. I believe it starts out as a Protozoan Scum, that feeds an algae growth, and if no rain event or good winds occur...it turns to a bacterial thing. Here is a thread that I replied to a couple years ago that has some good links to my other "scum" threads that may be of some interest to you...

https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=513675

I still do not have a solution aside from praying for rain every few days during the hot and dry portions of the summer.

Could the high levels of water circulation combined with oxygenated fast breakdown of organics in the bottom create too much of a nutrient load in the water column?

Maybe an Alum treatment would help lock up the nutrients to get things under control. Otherwise mechanical skimming/filter may help pull some nutrients out of the water.

At this scale, it is hard to tell if it is a blue-green algae bloom or not.

sometimes, obvious helps. cutrine plus early on a sunny day? and all other instructions followed? offering this because i was using at dusk instead of dawn...

Definitely spray early in the day vs. at dusk. Other than that follow the instructions on the bottle.

Plants/algae need to be actively growing for the product to work. Applying it at dusk right before they "go to sleep" doesn't help at all. If applied in the morning, you will see the algae starting to turn color in a few hours if applied correctly.

I've done the treatments mid-day (around 12). I will try earlier in the morning. Everything else with application has been followed by label and from support from the Sepro themselves. I've attached a better pic of the beginning phases of it forming again. This is 12 hours after significant rainfall. Will all be green by tomorrow.

field tile coming from a dairy farm? that is being fed from something....the algae at this point, i would give this year up and focus on the bacteria eating what they can w/o the copper setting them back.. your picture is what my pond looked like after 8 inches of rain cleaned the cows pasture and left the rinse water in my pond...