Had a pond dug a couple years ago approx. 50' x 70' , 10' deep in the middle. Have an aerator on the bottom, it's lined. How did you get a little ecosystem going. We put some cattails in a couple spots and i just put in a about a hundred fat head minnows yesterday. Will the small inverterbrate life just find it? There's waterskimmers and such all ready. Threw cattail seeds along the edge. Plan on getting brook trout, bluegills and hopefully channel cats. What do I feed the minnows to help them get going first and established before I get predator fish in there. I figure to toss in some cover and spawning boxes but what about feed for the minnows?

Friend of mine built some ponds on his place, after they filled he put those minnows in and by the next year there were thousands of them....so they found something to eat right away. The ponds were spring fed, he never fed them

Do some reading, then ask some questions

https://forums.pondboss.com/

www.pondboss.com is an excellent resource for pond owners.

Keith

we fertilized hatchery ponds with sheep manure, chicken litter and alfalfa meal to create a phytoplankton bloom which feeds the zooplankton

Be very careful about planting cattail, It will spread like wildfire and when they go dormant in the fall the vegetation will go in the pond and eventually fill it up very shallow, and nothing else can live in it. Same for moss like coon tail, or lotus.

A 10' deep, lined pond doesn't seem like good conditions for brook trout. It sounds like a better spot for warm water fish

He's in Montana!

I'm with BigBob on the cattails. We have a pond that has been over run with cattails. Eradicating them is difficult as you have to kill them below the water line or pull the root out. Then they come back the following year and you are doing it all over again. We finally hired a tract hoe to come in and re-dig the entire shore line.

If i was digging a pond I'd plant some evergreens in it before it filled in with water. I'd throw every field rock and boulder in there I could lay hands on. Id sein for crawfish and catch frogs. Minnows like you did already which I assume you have to be funny about what kind they are and I'd start catching and releasing some of my favorite dandys. Small mouth, perch, red ears. I got a low spot picked out, likely hit a spring, I just haven't dug mine yet.

The best farm pond I ever fished had large boulders scattered throughout for structure. I think it helps with temperature too. Heck of a spot. The guy that had the John Deere dealership in the 80's selling all those snow blowers and lawn tractors you see used for sale these days bought that place back in the day. If you got permission to fish in there you were blessed. Best example of a fishing pond I ever seen.

Buy some RTU Sonar herbicide. Make short work of any vegetation in the water effortlessly ! Once treated it will take several years for them to return .

Cattails suck

Catfish will become very predatory. They will eat everything in your pond if you let them get big enough. If you feed - they will get all the food

Their roots can destroy a pond liner also

You don't need to plant cattails ducks and geese will bring in enough seeds to give you more then you will want.there a pain in the arse and like mentioned you basically will have to pull them up by the roots or spray them even then they will keep coming back.spray is expensive and won't get any cheaper.

In Montana it will winter kill is my guess only 10 feet deep unless you have a constant flow of fresh water. In the summer you may have fish soup when it gets hot especially trout.

Ten foot that pond will be full of algae which will pull out the oxygen also cattails will fill most of the pond in very soon.

I went to every friend I had with a pond right before spawn and caught a few bass and bluegill and stocked my pond... They spawned in my pond...

Fish got pretty skinny the first year but after that all were fine..
Been 5 yrs and I'm gonna start grabbing a meal or 2 of bluegill and a few bass every year now just to keep things growing now that it's established

Plastic is bad for the environment,,,,
Next time clay line it

There use to be cattails in our pond but they died out for some reason. Maybe the watershield killed them. Not sure.