Over the years of blogging about my stock-tank ponds (a 100-gallon container pond in my former garden, and this new 717-gallon one), I’ve been asked many times how I constructed them. I finished the new pond yesterday evening, so I’ll explain how I did it, from start to finish.
Setting up the stock tank
If you live in the Austin area, go to Callahan’s General Store to pick out your stock tank. If you live elsewhere, I suggest searching for farm- or ranch-supply stores on the outskirts of town or looking for a mail-order source. Stock tanks come in many sizes and can be either circular or oval. I recommend a 2-foot-deep tank if you plan to grow water lilies and keep fish.
Measure an area a few feet larger than the size of your stock tank, and dig out the grass or groundcover down about three inches. Using decomposed granite or builder’s sand and a level (rest it on a long, straight board to check the level across a large distance), lay a flat, stable base for your tank to sit on. It will be very heavy when filled with water, and you want to be sure it won’t sink on one side over time, making the water line in the pond look tilted too.
When the tank is positioned, fill it with clean water from a hose or, better, a rain barrel. If using tap water from the hose, let the water sit in the tank for three or four days before planting or adding fish so that the chlorine in the water has time to evaporate. Once you have fish or other wildlife in your pond, you’ll need to be careful about how you add water to compensate for evaporation. To top off small tanks like my old stock-tank pond, use rainwater or a bucket of tap water that has had time to de-chlorinate. Larger tanks like my new one may be topped off with water right out of the hose if it’s only an inch or two; the volume of water in a large tank nullifies the impact of the added chlorine, so long as it’s not too much.
Planting the stock tank
You’ll want to choose at least three types of plants for your new pond: oxygenators (submerged plants), marginals (water’s edge plants), and deep-water aquatics (plants that sit on the bottom and have leaves on the surface, like water lilies). Water lilies may be sexy, but the hard-working oxygenators are very important in maintaining a natural balance in the water, keeping algae at bay, and producing oxygen for fish. I like to use anacharis, pictured above. The nursery will sell it in small bundles wrapped in wet newspaper.
As soon as you get home, put the plants in a bucket of water or get them planted in the pond. You’ll need a few old plastic pots filled with clean pea gravel. It doesn’t matter whether the pots have holes in the bottom. Pick up a clump of your oxygenator plants…
…and carefully insert the bottom inch or so of the stems into the pea gravel of the pot. The stems are fragile, so I make a little hole in the gravel with my fingers, set the stems in the hole, and then bank the pea gravel around them.
Here’s a bunch all potted up. Anacharis doesn’t even have to be potted, I’ve heard, but doing so helps protect it from being devoured by the fish. The fish may eat it up over time. When that happens, just buy some more.
Place the potted oxygenator plant on the bottom of the tank, and that’s it. I bought six bundles of anacharis for my large stock-tank pond and filled three pots with them. I may need more, but I’ll wait and see if these grow fast enough to keep the tank clean.
Next you’ll need to build some platforms for your marginal plants. I use whatever is at hand: stacked bricks, overturned pots, and cement blocks.
Cement blocks with holes in the middle have the added advantage of giving fish a hiding place from predators like raccoons and herons.
I chose three marginal plants for my new pond: dwarf papyrus (brought over from my old pond)…
…’Black Marble’ taro…
…and this plant generically called “pond lily” by the guy who helped me at Hill Country Water Gardens.
Last but not least, the attention-getters for any pond—water lilies. Deep-water aquatics like these shade the water with their large, spreading leaves, helping to keep the pond cool, sheltering fish, and blocking out the sunlight that algae feed on. I brought over ‘Helvola‘, a dwarf yellow, from my old pond.
And I recently bought this ‘Colorado,’ a medium-to-large coral-pink lily. When purchasing water lilies for your container pond, be sure to note their mature sizes. Small stock-tank ponds like my old one have room for only one dwarf water lily. Larger ponds may be able to support two or three larger lilies.
Water lilies should be placed on the bottom of the tank if their leaves can reach the surface. If the leaves aren’t that long, place the pot on a few bricks to lift it up. As it grows, remove the bricks to lower the pot to the bottom of the pond. Once a month during the growing season (March or April to October in Austin), press a fertilizer tablet with your finger deep into the heavy soil of the water lily’s pot. Don’t let the tablet dissolve in the water, or it will contribute to algae bloom.
In Austin’s climate, hardy water lilies (as opposed to tropical ones) can be overwintered in the bottom of a 2-foot-deep stock tank. The water lily will die back to mushy stems in the winter, which should be collected and discarded from the pond. Every year in early spring, as new growth begins, divide your water lily and replant in heavy clay soil in a pond pot with no holes in the bottom. Top-dress the pot with pea gravel to keep the soil from floating into the water. (I’ll write a post next spring about dividing water lilies.)
Bird-bathing and insect-drinking platform
With their sheer sides and lack of natural shelves, stock-tank ponds have the advantage of being difficult for raccoons, dogs, and cats (and small children) to get into. But it’s good to make your pond hospitable to birds, insects, and other small creatures that might want a drink or a bathe, or that fall in and need a place to crawl out. I put a stone bathing platform on top of a cement block next to the edge of the tank. It gives birds and insects easy access to the water, and I can enjoy watching them enjoying the pond.
Fish
I will add fish—native gambusia or hardy goldfish are good choices—for color and life in the pond, and for eating mosquito larvae. In fact, I never feed my goldfish, letting them forage instead on mosquito larvae, algae, bugs, and the anacharis at the bottom of the pond. Check with your supplier to find out how many fish your size pond can support. If you don’t want fish, you’ll need to rely on mosquito dunks or bits to keep larvae from hatching in the water.
Maintenance
The only maintenance is netting fallen leaves from time to time, fertilizing once a month during the growing season, mucking out the bottom once a year, and dividing plants once a year. Expect an algae bloom—the pond will turn green—soon after you plant your pond and maybe each spring as the water heats up. But by keeping the pond stocked with oxygenator plants and being patient until the water lilies leaf out to shade the water surface, you’ll find the water clears up on its own without need for any chemicals. Just as nature does it.
Update: August 15, 2009. Here is how the pond looks after only a few weeks.
Disclaimer: This post details what has worked for me in making a stock-tank container pond in zone 8b. Gardeners in colder zones may not be able to overwinter pond plants or fish in this way.
All material © 2006-2009 by Pam Penick for Digging. Unauthorized reproduction prohibited.
I am inspired! What a great post, and your new stock tank pond is beautiful.
Comment by Carol, May Dreams Gardens — July 14, 2009 @ 7:07 am
Thanks for the detailed information. I have a crass question if you will. About how much does a stock tank cost?
This 8-ft diameter tank costs around $300. I believe I paid less than $100 for my small 3-ft diameter tank several years ago. —Pam
Comment by Les — July 14, 2009 @ 7:07 am
Pam it looks great! I didn’t know about the oxygenator plants. I’m going to read up on it some more.
Comment by Randy — July 14, 2009 @ 7:20 am
Thanks for the tutorial Pam. Keep us posted on how the pond looks from week to week. Is it in some shade because I am wondering at the temperature of the water in our brutal summers?
Yes, it is in partial shade, Jenny. My old, smaller pond got full morning sun and afternoon shade. However, the one at the Wildflower Center is in full sun all day. They banked soil up high on one side of that tank to moderate water temperatures. —Pam
Comment by Jenny — July 14, 2009 @ 7:31 am
Pam, this looks great. Thanks for the photos. It makes me want to take a trip over to Callahan’s. Do you have any idea yet how often you will need to fill it? Do the plants slow down the evaporation? My vegetables in stock tanks have been doing well until the last couple of weeks with the extreme heat. They are shutting down and hoping for the best. Except for the corn which is about 4 feet tall.
Shade slows down the evaporation, so I think the plants will help reduce it as they fill in. I’ll post a weekly update on the pond and try to remember to comment about the evaporation. —Pam
Comment by Shannon, another Austin gardener — July 14, 2009 @ 8:32 am
This is a terrific idea! I love the look.
Comment by Darla — July 14, 2009 @ 9:20 am
Congratulations on your pond — it looks great! Such a soothing, refreshing thing to gaze at in this extreme heat.
Comment by Anna/Therabake — July 14, 2009 @ 10:33 am
That looks really nice! Again, I would have never thought about using a stocktank for a pond.
Jake
Comment by Jake — July 14, 2009 @ 10:51 am
Love it!
And thank you for writing in such careful detail about the whole process, it’s very inspiring! I’m tempted to run out and find a stock tank myself this very instant…
Comment by arythrina — July 14, 2009 @ 10:56 am
The other benefit to a bird-bathing platform is it provides a way for frogs to get out once they get in. For large frogs, the lily pads don’t seem to provide enough buoyancy for them to be able to jump out. This may be less of an issue with a stock tank (can they jump up into it in the first place?), but we definitely saw this in in our small in-ground pond.
Hi, Mark. I didn’t know you were blogging. Thanks for commenting. We had an occasional toad in our old pond, which was the same height as this one. I don’t know how they managed it, but I guess they are good leapers. I have heard from another local blogger that frogs get in his tank pond and spawn to excess. It’s something I’ll be looking out for. —Pam
Comment by Mark — July 14, 2009 @ 11:01 am
Thank you Pam! I am so lucky to have you as my project mentor! I think I will make this our August project (shh, don’t tell the husband, I need to sneak these things up on him). I am a little worried that the place we have designated for the pond is a little too shady, although I imagine there are probably shade plants I could use too…just no water lilies, right?
Water lilies need sun, I’m afraid. But there are plenty of pond plants that will take shade, including the taro I just purchased. The biggest hassle of placing a pond in the shade of trees is the leaf litter that must be mucked out. I’ll be dealing with that myself since this pond is in partial shade under live oaks. —Pam
Comment by Loree/danger garden — July 14, 2009 @ 2:42 pm
This is a keeper blog post for me – can’t wait to give this a try a little later down the road. Thank you for the helpful details, and enjoy!
Comment by Kelly Jennings — July 14, 2009 @ 2:51 pm
Pam, Thank you for the instructions! Your pond looks wonderful. I did learn from the local aquatics/pond folks that tropical lilies would love the pond in the summer, but unless i insulated at least one half forget goldfish…they need cooler water. gail
Comet goldfish survived in my little stock-tank pond for several years, Gail, and it was not half-insulated. It didn’t get much afternoon sun, however, which I’m sure helped. Even if you can’t have goldfish, though, I bet gambusia, or mosquito fish, would live. Nashville can’t be as hot as Austin. Can it? —Pam
Comment by Gail — July 14, 2009 @ 3:14 pm
Hi Pam, your how tos are always so well thought out, taking us step by step into the process. The plantings already look terrific and the colorful fish will be icing on the cake. :-)
Frances
Comment by Frances — July 14, 2009 @ 3:30 pm
Does it overflow with rain?
It can—if it ever rains in Austin again. ;-) It’s never a gush of water though. Just a light sheet of water that cascades down the sides of the tank. —Pam
Comment by Becky — July 14, 2009 @ 3:39 pm
Love it Pam!! I have anacharis grass in my pond. The fish nibble on it (it is not in pots), but do not destroy it. It lives all winter under the water, and multiples in spring. I always try and give some away. I have hardy goldfish that do great–as long as a certain pesky blue heron doesn’t stop by for dinner. :)
You did a wonderful job on the stock tank pond. I love the rustic look!
Comment by Linda at Meadowview Thymes — July 14, 2009 @ 4:02 pm
Great description and some good questions from other bloggers. So, no moving water in it? the fish will create all the ‘movement’? Really neat.
Yes, the movement will be up to the fish. I had a bubbler pump in my previous pond, but I’ve decided to let this one be still water. —Pam
Comment by Janet — July 14, 2009 @ 5:04 pm
Your ‘how-to’s’ are always so good – and they always make me want to do whatever it is that you have shown us how to do! I still have bookmarked a stone patio that you made (and I hope to do it sometime over the next year). One question: do you ever find snakes in your stock tank ponds?
Oh – I just left a comment at Annie’s: I saw on the evening news how terribly dry Texas is. I know that is difficult on farmers, gardeners, everyone! We’ve finally had a summer with some rain, after a dry two years – but I hate to hear that you guys are struggling. It said that some areas around the Hill Country are two feet below normal – that’s tough! Hang in there.
Eek, no, I’ve never seen a snake in there, Pam. Now I’ll be wondering if they can get into it! Thanks for the drought sympathy. It’s awful. I’m pinning my hopes on fall rains from an upcoming El Nino weather pattern. —Pam
Comment by Pam — July 14, 2009 @ 6:03 pm
Very nice and thorough post. I do some backyard ponds (in Michigan) and you have covered the subject very well. Just having a water feature in the yard in your heat must be refreshing. I think I’d have to wade in it now and then…or maybe even sit down. You know, like the reverse of the northern craze for outdoor hot tubs in the winter.
Comment by Sande — July 14, 2009 @ 7:07 pm
I’m so impressed. Your pond looks like a cool drink on our hot summer days. You should come put one in my yard in your spare time!
What spare time, Diana? I’m working hard at lounging in the pool this hot summer. Aren’t you? ;-) —Pam
Comment by Diana — July 14, 2009 @ 9:28 pm
I love your bathing platform. And I hadn’t thought about the advantage that stock tanks have over in-the-ground ponds when it comes to racoons. In my old pond I never put the oxygenators in pots, which may be why I was occasionally having to remove some of it; they went wild! My old pond also didn’t have any fancy pumps although I found adding a small solar water fountain in summer helped add oxygen for the fish (comets). Your tank really looks great and it’s going to be such an enjoyable addition to your backyard. Congratulations!
Comment by Jean — July 14, 2009 @ 10:33 pm
“It doesn’t matter whether the pots have holes in the bottom” You mean drainage isn’t a problem?–lol. It’s beautimus. That tarot is particularly beautiful! And that’s a great point about the cinder blocks providing shelter for fish.
Comment by chuck b. — July 14, 2009 @ 11:05 pm
Your new stock tank looks great, Pam – and your detailed post with its clear explanations is a gift for any Austin gardeners who want to know how it’s done.
It’s such a big step! Does seeing the water in the tank make you feel at home in the new house?
Annie at the Transplantable Rose
The new pond blows away my old one, Annie. Bigger IS better! The kids and I are already enjoying our twice-daily visits to see what’s going on in it. —Pam
Comment by Annie in Austin — July 15, 2009 @ 11:04 am
You did get a colocasia/alocasia. Looks good and should be safe in the pot. They send surface runners out of the pot, I think, but are very easy to control. It should be fun to watch it all grow in.
Comment by ryan — July 15, 2009 @ 11:33 am
I am not about to tackle this project, myself (lack of room) but I’m SO glad that you posted such a thorough explanation of the whole process Pam. It was very cool to follow along!
Comment by Blackswampgirl Kim — July 15, 2009 @ 2:36 pm
Pam, what they dubbed Pond Lily looks like the red-leafed Crinum to me. I have two of them in my bog area and have been a little disappointed in their growth habit. They may need more sun than they’re getting so I’m not giving up on them yet.
Hmm, I don’t know, Cindy. The leaves on mine are much thinner and strappier than those of the red crinums I saw pictured online. Time will tell, I guess. I hope yours settle in and start growing for you! —Pam
Comment by Cindy, MCOK — July 15, 2009 @ 7:12 pm
You did such a beautiful job of explaining this that I read every word and completely enjoyed it, and I don’t even have a pond, nor do I have plans to get one in the near future!
Comment by anna maria — July 15, 2009 @ 10:51 pm
It just occurred to me to mention that hail will shred Colocasia in a uniquely bad way. I’ve had to cut mine to the ground after a light, sissy San Francisco hail storm; I shudder to think about what a Texas hailstorm would do. The good news is, they’re indestructible and come back in a week or two. FYI.
Comment by chuck b. — July 17, 2009 @ 1:03 am
Fabulous post! I bookmarked it so I can revisit easily. Think I’ll print it too…
Thanks for the details–from where to get a stock tank, siting and filling, to how to plant. You answered so many questions…I’ve always wondered how to keep a still pond from being overrun by algae.
I’ll be e-mailing this link to my friends.
Comment by Kathleen Scott — July 17, 2009 @ 4:55 pm
Pam, great details on this step-by-step. Thanks so much.~~Dee
Comment by Dee/reddirtramblings — July 19, 2009 @ 7:26 am
Using the stock tank is such a great way to display aquatic life closer to eye level. This is so beautiful! Do you anticipate any problems with fish or plants being swept over the sides in a crazy Texas rainstorm?
It never happened with my old stock-tank pond, Kat. When we do get heavy rain (it’s been so long!), if the tank overflows, it just lightly sheets down the sides. Now I did have a fish jump out of the pond once… —Pam
Comment by kat — July 22, 2009 @ 3:03 pm
All-right! I’ve got two small stock tanks sitting in my front yard just waiting for someone to tell me how to make them into ponds! Pam to the rescue, as always. Thanks so much. Your pond is wonderful.
Thanks, Mamaholt. Good luck with your pond! —Pam
Comment by Mamaholt — July 23, 2009 @ 1:21 am
Such a well-written, informative post! I’m printing this off for future reference, even though we’re in different zones. The method would pretty much be the same. I hope this does really well for you.
Comment by Nancy Bond — July 23, 2009 @ 10:57 pm
I found a stock tank at Tractor Supply. 6FT x 2FT Round. This will be the new home for some of my water lilies and goldfish. I am having two in the ground ponds (8×8) and (8X4) removed next Monday. They’ve been neglected for years and are now home to what sounds like hundreds of tree frogs at night, overgrown lilies and bunches of floating plants. All this in preparation for a new raised bed vegetable gardens.
Good luck with your reworked ponds, Jacqueline. —Pam
Comment by Jacqueline D'Elia — July 30, 2009 @ 4:02 pm
if it overflows with water get a drill and drill about 3 holes just avove where you want the water to stay and wen it rains the water will just go through the holes and you goldfish wont get damaged. also it is a well nice pond.
Comment by oliver brisby — August 22, 2009 @ 1:58 pm
Ok, I hope I didnt miss this question already being posted… Would you recommend a pump/filter for when you add fish or do the oxygenated/ing plants take care of keeping the water healthy? Do you know if there are filters that hang on the side of the tank, like an indoor aquarium, or do you just get one that sits on the bottom? Thanks
In my experience with a 3-ft. diameter tank and an 8-ft. diameter tank, you do not need a pump or filter to keep the water clean for fish. If you live in a hot climate, you should try to give it a little shade in the late afternoon or else bank soil up on one side to help moderate the water temperature in the summer. But all you really need to keep the water in balance is plenty of oxygenating plants underwater, shading plants (like water lilies) on the surface, and the proper number of fish (too many fish is bad for water quality, not to mention the fish). Check with your fish supplier regarding the right number for your size pond. Since I’ve not used a filter, only a bubbler pump, I can’t make any suggestions about that. Good luck with your pond. —Pam
Comment by Brian — November 19, 2009 @ 3:14 pm
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So you don’t have a water feature in the pond? I already have the tank sitting in the ground but it is empty and sad looking from a previous owner.. Guess I can just do it with out a running a water feature. Yours looks awesome. What about the fertilize for the plants you have a pic up.. Hope I can find something in Roswell, NM. Since I don’t live in Austin anymore..
Hi, David. The only water feature is the water feature, i.e., the pond itself. No pump, no fountain, no bubbler. It works great and is self-regulating once you achieve the right mix of shade plants, underwater plants, and fish (see details in my post). I’m not sure what you’re asking regarding the fertilizer; can you rephrase? Any pond nursery should carry what you need. If Roswell doesn’t have one, perhaps a road trip to Albuquerque with a couple of coolers to carry home your watery supplies in? Also, since you’re in a hot, dry climate, it might be best to site your pond with morning sun but afternoon shade to keep the water from overheating. Banking soil up on one side of the tank helps regulate temperature also. Good luck! —Pam
Comment by david smith — March 29, 2010 @ 1:32 pm
I enjoyed reading this very much. I live in Miami and thinking of doing a pond like this . The “soil” here is rock thus rather not dig plus plan to put it next to house in areas that gets mostly shade.
I do plan to use pond liner as not sure how safe metal would be with fish but the trough as the frame is a great idea.
Thank you
Comment by Sal — May 6, 2010 @ 2:02 am
LOVE THE LOOK, AND LOOKING AT YOUR POND ANSWERED THE QUESTIONS I NEEDED….WHAT PLANTS TO PLANT WITH PEA GRAVEL..AND WATER TURNING GREEN….LET CLEAR ON ITS ON…..I WAS USING TO MANY CHEMICALS THAT WAS KILLING MY FISH….THANKS NICHO
Comment by DORNICHO MCGEE — June 2, 2010 @ 8:27 pm
I’m in southwest Austin, and I’m considering adding a smaller stock-tank pond to our yard this summer. I’d love to see pictures of your smaller pond, as well as pics that show how your larger pond is doing this year.
Thanks!
Robyn
Robyn, thanks for your interest. I post pictures frequently of my stock-tank pond. Click the link for my most recent pics, or click on the category “stock tanks” in my sidebar to find all my posts about it. My smaller stock-tank pond in my former garden can be found within that category, or click this link for one picture of it. —Pam
Comment by robyn — June 7, 2010 @ 1:24 pm
I love this pond! I would love to do something like this, but I am concerned about the bottom of the tank rusting out. I *think* this is inevitable, do you have any sense of how long it takes or if there is a way to avoid it happening?
I think rusting is inevitable too, John, and I don’t know of any way to prevent it. However, I think you get a pretty long life out of these tanks. The best way to find out, I suppose, would be to call Callahan’s General Store in Austin, which sells stock tanks and caters to ranchers, and just ask. —Pam
Comment by John B. — June 11, 2010 @ 11:52 pm
Hi Pam,
I am truly inspired! I do have a question. I live southwest of San Antonio TX–but it can still get fairly cold here. What recommendations do you have for overwintering fish and plants in my area–based on the size of the tank?
Cindy
Cindy, here in Austin, which gets colder than your area, my goldfish overwinter in a 2-ft deep tank with no problems. Just make sure you stop feeding them, if you feed them at all, by the time temperatures cool down. They’ll semi-hibernate at the bottom of your pond and won’t need food until the water warms back up. Hardy water lilies will just go dormant on the bottom of the tank through the winter. My marginal plants (the ones sitting on cinder blocks near the surface) have been a mixed bag. I lost my taro and pond lily last winter (I replaced them this spring), and the dwarf papyrus has been slow to recover. —Pam
Comment by Cindy — June 15, 2010 @ 12:48 pm
Another question…Tractor Supply has the Rubbermaid stock tanks, as well as the metal ones. Are the Rubbermaid tanks OK to use?
I don’t know anything about them, Cindy. —Pam
Comment by Cindy — June 15, 2010 @ 1:37 pm
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