Pond Boss Forums GENERAL QUESTIONS Help Need help with pond

Hello, I am new to pond maintenance/care and was looking for some help/advice with my pond. I have a roughly 60’x100’ (9-10 ft deep in center) pond that’s in rough shape right now. The pond is completely covered in floating algae. The water is a bluish green tint with some visibility. The pond has not been aerated in about 5 or 6 years and when it was, it was with a surface fountain the previous homeowner left us. The fountain gave out and the pond has just been sitting ever since with little to no care. I was doing some research into pond aeration and decided to purchase a hiblow hp60 pond aerator. I have it set up and am ready to go but my main concern is causing a fish kill. The pond contains bluegill and largemouth bass. I’ve read it is best to start at 15 minutes a day and double the time each day. I’ve read posts by other users that have done this method and still had a large number of fish die. I’ll link a picture of the pond below and maybe someone could recommend what’s best. I planned on pulling out the floating algae by hand once I had the system running. There is visible algae/plant growth from the bottom of the pond as well. Beyond aeration and removal of the floating algae, I’m not sure what else I should do to take care of this pond. My main concern is keeping the fish I have alive and well. Thank you for any and all help

Welcome to the forum. Unfortunately this time of year is our busiest time of year and I don't have time to go into a detailed explanation. Cliff notes are you will need to do your research on the DIY system in regards to the CFM of the pump at that depth and how many gpm your diffusers will bring to the surface with that pump. You want to bring between 100% and 250% of the water volume in your pond to the surface every 24 hours once the system is running fully.

If the system is sized correctly, and the start up procedure is followed you will not have a fish kill. You are correct. 15 min day 1, 30 min day 2, etc. etc, until running 24/7. If you smell hydrogen sulfide on any of those days, run it the following day for that previous day's time, and continue to do that daily until you do not smell the hydrogen sulfide any more. Then you can continue to ramp up the run time.

esshup is one of our experts on this topic, I would recommend trying to follow his advice as closely as possible.


I am only commenting because some of the algae that is blue-green in color can be a type of cyanobacteria. It can be harmful to dogs and humans, but I assume no person is going swimming when the pond looks like that!

However, please don't let your dog swim in there when the dog is "helping" you install and run the aeration system.

Good luck on cleaning up your pond. The best way to eat an elephant is one small bite at a time. If you take small steps, you might have a nice jewel of a pond in a few years!

I would try to manually remove some of the - what appears to be filamentous algae as a start. That would remove some of the excess nutrients and provide room to take additional actions (aeration, chemical or other).