Odd-ball concrete pond - beginner

[AussieGardener]

Hello all,

Marvelous forum, glad to be here. We're in the Maryland area, wanting to get up to speed on an abandoned concrete pond at our new address. Soil and silt is currently washing into it from upslope (I have probably dug out 2 tons of flag iris as I did the initial muck-out, intense exercise!). I estimate that the pond volume is 900 gallons, but with an average depth of aprox 11". It's basically a concrete hole in the ground, and although power has been dropped right next to it, there's no functioning pumping or filtering equipment. (I found a dead aerator unit, and I'm going to try cracking it open and see if it can be serviced at all).

We have an absolutely burgeoning frog population, probably 5 species, incredible chorus at night, and this brings me to my first question - are fish essential to a healthy pond? I am aware of the advantages they deliver in terms of nutrient cycling, but for the first year, we'd be perfectly happy to continue cultivating a variety of water plants, and enjoying all the antics and sounds of these surprising amphibians. (I assume that skipping a fish population means a simpler maintenance routine overall).

I'm currently arresting deteriorating water quality by transferring rainwater out, and then putting fresh(er) rainwater in. As the water warmed up, I noticed it starting to stink. Oops. I suspect that the frogs are surging because I am only working with captured rainwater, not chlorinated tapwater.

The soil influx issue also means of course that we have land upslope, so over the longer term, I would like to plan a waterfall.

PS : lots of other beginner questions, including appropriate equipment needed (pump, filtering, etc) but I assume a further exploration across the various sub-forums will yield the answers I need. All the best!

 

[IPA]

Great picture of the frog. The is no reason to feel you should have fish. I’d recommend investing in a good pond water test kit, drops, not the strips. The tadpoles and frogs will produce ammonia so it will eventually cycle. Maybe want to add a little baking soda to the water or use some crushed oyster shells but that all really depends on the pH and KH.
I like the API Pond Master kit. Ammonia, Nitrite, Phosphates, and wide range pH. I also purchased the GH & KH kit. For the money they are good kits but not the only ones out there.

 

[j.w]

@AussieGardener
It's a bit shallow for fish as you get some freezes there and you'd have to use some kind of cattle heater or something to keep the water from freezing solid or bring the fish inside for winter. You can make a really nice looking pond for plants and critters. The pond has great bones as long as it does not leak.

 

[Mmathis]

Hello and welcome!

No, you don’t have to have fish. The only advantage I could see would be taking care of any mosquito larvae that ended up in the water — however, if you have water movement, mosquitos shouldn’t be a problem (they are weak flyers, and prefer calm, stagnant water).

When filled all the way to the top, how deep is it?

 

[addy1]

Welcome to our forum!

That is a neat looking pond. What part of MD are you in? I am out in Frederick.

 

[sissy]

neat pond and nice that it is shaded but leaves could also be a hassle so you may have to cover it .Do you know how deep it is as it looks like it could be sloped .I have seen pools like that for children and wonder if there is some type of piping in it .My neighbor had something like that back in NJ for her 6 children ,taxes were cheaper since it was not deep and she did not want a pool ,plus insurance was cheaper on it .I may have pics of it somewhere ,my son used to love it .

 

[Tula]

Very neat pond I think it would make a wonderful nature / wild life pond....plants, frogs, place for birds to bathe and drink etc. It could be very beautiful and yes, less work than if you had fish.

 

[AussieGardener]

Wow, thank you all : IPA, JW, Mmathis, addy1, sissy, and Tula. I have lots of good information here. I am glad to hear from amongst you that fish are not required (I was beginning to take away that impression after seeing various explanations of their participation in nutrient cycling etc).

Sissy, the idea that this may been a custom kiddie pool is quite interesting, and I had not thought of that. That would explain the odd shape (not naturalistic looking as you'd typicall want for a pond), the 'shelf' all the way around the perimeter. It has a slightly sloped bottom - ranging from 9" in the shallow end, to 14" in the deep. Whoever poured this one was slightly off level - less than an inch, but it shows when rain fills it.

As for the existing fittings, I have found a short copper pipe that comes up vertically from the bottom, and it comes off a split on one of the outside water lines. Although I have filled this 'pond' with captured rainwater so far (roof to pool, then pumped from pool to pond... the pool is a whole other story, but currently a haven for frogs and frogs-to-be), I do have the option to add some clear water, which I did today - with temps rising and the water getting darker by the week.

Sissy, there are also the following fixtures and features

1. an apparent overflow outlet (partially blocked as I can tell, but set under the surrounding patio and is fitted with 1 ½' heavy duty black plastic piping)
2. what appears to be a brass disc, fitted to the pond floor, and I think seated over a gasket. There's a brass hex bolt tying it down - I may undo it and see what it represents. Perhaps a drain fitting? To where?....
3. Another copper or other metal tube that feeds into this pond thru a sidewall. I don't know where it comes from. It is connected to the side of the pond that backs onto the upslope part of the yard.
4. Some short copper pipe fittings, one ending in a tee-piece.
5. External to the pond itself, but associated with it, was a standalone and electric plug-in type aerator. I found the 'puck' buried in the mud at bottom of the pond. The unit doesn't work. I have opened it up and it's heavily corroded inside... it was then that I recalled that when we bought this place, it was actually IN the pond (perhaps someone mistook it for a submersible unit). I am going to try to revive this on the bench, but I don't give much for my chances. Worth a shot before buying a replacement. It may have been in water for years....

With an estimated volume of just under 1000 gallons, the immediate concern is to get the water moving and filtered. Bog filtration looks interesting, and I wish to learn more, but I don't think there's time to build that before the frogs get into trouble with water quality. I will search over the rest of the forum for recommendations on a starter pump/filter kit, and while that is coming to us, learn more about what frogs need for habitat etc. But based on the numbers and their enthusiastic dusk calling here, I'd say they're pretty happy as is! (2 more morning pics attached here, as they quickly find and setup shop in each set of aquatic plants we land. These critters are super entertaining, and we even have them overhead (at a good height in trees on the lot)).

Addy1, we're in Colesville area of Silver Spring (20904), within a few blocks of the intersection of Randolf and New Hampshire Avenues. If you find yourself coming down this way, please PM me and we'll plan a quick walk and talk here - maybe with a cold drink on spaced chairs to follow!

All the best everyone. I hope you all have a day with weather as beautiful as it is here. Cheers!

 

[addy1]

Addy1, we're in Colesville area of Silver Spring (20904), within a few blocks of the intersection of Randolf and New Hampshire Avenues.

I lived 21 years in Rockville, Broadwood and Viers Mill Rd. Used to walk to Twinbrook shopping center for candy with my siblings. Went to Rockville high school, left to go to AZ for college, ended up in Phoenix working until moved back to marry new hubby, when my other one passed.

The frogs etc can tolerate really yucky water, well what we would call yucky. Think natural stagnant ponds, they do fine. But you would be happier with it looking and smelling better.