In late summer of '18 I drained my small pond completely dry and made repairs, installed a new overflow system, did maintenance to the aeration, etc. Fish were removed.

A neighbor had put rock bass into the pond (he thought they were BG!), which then required predator fish to control (LMB)….and things of course got out of control. I did not and do not want fish in the pond as it is just too small, and requires frequent treatment to keep it clean and balanced.

Pond refilled nicely by early spring, and I've been working to keep the quality good. Have a lot of happy frogs, salamanders, and a few sliders.

FF to now. Even though the pond was dry for nearly a month last year, I can now see hundreds of 1 to 2 inch long minnows around the banks.

Not sure how that happened, but I need to get rid of them now while they are very small. If I didn't dream it, I once saw here info on using hydrated lime to exterminate fish. Searched, but could not find the info. Can someone point me in the right direction? TIA!

They are probably Gambusia (mosquitofish). They will keep the pond from becoming a mosquito pit. They will not damage water quality at all. I would leave them be.

+ 1 on the gams.... if that’s what they are.....they will keep the small bugs down to say the least. I have them and are very glad
They get about 2” long

Thanks for the replies. I'm not sure they're gams. Didn't have them in the pond previously, and they probably didn't show up in such numbers in such a short period of time. My H also saw 3-4 LMB fingerlings hanging around the rocks. I'm guessing hatchers from eggs that survived the draining/drying process??

At any rate, I did find one thread that touched on using hydrated lime. Still searching, but it sounds as if the pond has to be DRAINED again in order to treat it with HL. Is that correct?

Draining the pond reduces the area of water and thus reduces the amount needed to effective kill the pond.

What are your goals for this pond?

This will be and ongoing problem as fish and eggs probably flowed in from a BOW upstream.

If this is the case, killing the pond will be a futile and useless task.

That's what I figured, re: draining. The pond was completely dry for a month, and I still have minnows. Which sort of tells me that treating a small pool after draining still might not do the trick. UNLESS everything that's going to hatch has hatched, and there's nothing big enough in there now to have spawned and deposited.....

I sure hate to drain because I used quite a bit of bentonite in the reconstruct. I've read it's not good to let it dry out.

The goal is not to have a fish pond, beyond maybe a few diploid grass carp, but an attractive water feature. At a little over a quarter acre surface and 8' at the deepest, it's simply not big enough for game fish when we are not fisher types. Looking after fish is actually a pretty big job.

There is really no reason you have to manage the fish in the pond. I would venture that over 90% of ponds or receive very little if any management. Just a thought.

Heck the fish can take care of themselves pretty much especially if you don’t fish

You might find occassionally throwing a little feed to whatever lives there to be quite relaxing as well.

Even if I only had a tiny little water garden pond, I'd go find some GAMs to keep the mosquito hatches down. A very beneficial minnow, indeed.

I wouldn't worry about it then if there is no management planned. You aren't going to be able keep sort of fish out of there 100% of the time.

Just a note on what happens to a pond without fish...My 1/4 acre pond was stocked with minnows only for the first year and the amount of frogs/tadpoles/snakes/turtles/bugs/crawdads that filled the pond up was scary amazing (basically the critters that fish tend to eat/control). Now, with predator fish in the pond, the over populations of small critters is greatly reduced.

You should consider embracing some fish life as part of the balance. Mostly, the worst that could happen is your pond ends up with a population of "smaller than usual" BG and/or LMB. Heck, even check into the HBG and HSB route (less reproduction).

If a fishless pond is very important to you, you can expect to produce an environment that will thrive with the smaller creatures and that could be truly exciting too (if you don't mind the potential exoduses that can occur as young critters leave the pond to explore their options or the amount of mammals (raccons) that may come to the pond for small critter meals) .

If your pond is getting fish from the water the feeds into it OR they are swimming up from below the drain pipe, then your fishless pond dream will be a struggle. You may have no choice but to embrace the fish and do what you can to manage them. If your pond was dry (meaning no puddles) for a month...the only fish that I know of that might carry through would be from the catfish families and they still need ample wet mud and preferably in the cooler/colder seasons.

Catch some of these fish, put them in a jar, photo them and let's see what you are dealing with...minnows would be a good part of a small creatures environment.

Your project sounds very cool btw!

Kind of an interesting perspective on fish management... So if you wanted stunted fish in a pond..... couple of Bluecat and crappie?

We have .25ac pond that was renovated but never stocked for 5yrs. The watershed is 100% from fields on our land and the downstream pond is 300+yds away with 50+ft elevation drop. After finding this site I decided to stock it with 4in HBG since it was completely ignored. 2 weeks ago I decided to see how they were progressing and caught several much larger GSF. Life finds a way. 2 other ponds stocked with CC now have lots of bass.

IMO you are going to have fish one way or another, so question is are you going to have a say in what type of fish that are in your pond.

Oh, I loved feeding the fish. I did it nearly every single day, spring through fall. 2 of the original LMB I stocked in would follow me around the bank.

A lot of the fish disappeared last year. I think there was a ph crash after an enormous amount of cedar needles got washed into the pond. Made a bad mess of it, not sure what else it could have been. Since the pond needed to be drained for repairs/modifications, we went ahead and removed the rest. Less than a 5-gal bucketful of LMB went to a neighboring farmer's pond.

ETA: So far as mosquitos are concerned, the aerator is big enough to keep the entire surface of the pond rippling 24/7. I assume that (and numerous frogs) keeps mosquitos disinterested in turning it into a nursery. But I do really like the idea of gams as a backup.

The pond is fed only by ground runoff. We threw in a minnow trap yesterday, will see what we catch. Good idea, getting a photo. Will do, and post here.


Keeping it nice really IS a "project". Constant fight with algae and weeds (despite aeration and beneficial bacteria additions), water level when we don't get rain for weeks on end, etc. Worrying about fish is not fun.