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Golden ponds

A healthy goldfish pond sparkles on a hot day, reflecting a blue sky and offering the visual delights of graceful golden fish and the heady aromas of water lily blossoms.

But the dream of a cool, inviting pond often turns into a nightmare of green scum, foul-smelling water and dead fish, despite the expense and hassle of pumps and filters and medications and changing the water over and over.

Gardeners can avoid that nightmare by meeting a few basic requirements to create a healthy, self-sustaining freshwater ecology that can't be duplicated by filters, pumps and chemicals.

Since 1984 I have helped dozens of clients either create or heal their goldfish ponds. I have seven ponds in my South Tampa yard, all of them perpetually clear. So let's review some pond basics.

Your pond is likely made from a butyl rubber liner, a rigid vinyl shell or concrete. Fill it with fresh water from your garden hose. Don't use softened or recycled water, both of which are high in salt.

Cover the pool bottom with 2 inches of rinsed pea gravel to harbor plant roots and crucial water-purifying micro-organisms. Let the water "age" for three to five days after you fill the pond to let sunshine and fresh air eliminate chlorine and other additives. Then sprinkle on the water a handful of Sunniland Palm 8-6-6 fertilizer to ensure ample nutrients for your water plants, plus two handfuls of dolomitic limestone to ensure adequate calcium and magnesium. That will also create the non-acidic conditions the fish, water plants and snails require to thrive.

Next, add a cup or two of the beneficial bacteria and enzymes sold at most aquarium stores or online, such as PondZyme. They are effective at digesting the wastes that foul so many ponds. They will quickly multiply and do most of the work for you for years to come. Skipping this last step to save money is a false economy. A healthy pond is dependent on good microbes.

Buy a few bundles of the native warm-water plant Hot Water Cabomba, or Fanwort (Cabomba caroliniana) and anchor them to the bottom of your pond with chunks of limestone rock. (The limestone helps keep the water non-acidic and slowly leaches out more calcium vital to the water plants, snails and fish.) This lovely plant is an effective living water filter. Drop some into an existing fouled pond and in less than a month you will see a big change in water clarity and a reduction in odor and algal overgrowth. If you plan to add goldfish, you know that they need oxygen as badly as you and I do, and I know of no other freshwater plant that so effectively oxygenates pond water.

To further ensure clean, clear water, treat yourself to native white water lilies, or those lovely fragrant purple tropical water lilies. Their roots absorb wastes such as dissolved nitrogen and phosphorus. Their lovely round pads are living "umbrellas" that offer shade for your goldfish, which dislike overheated water. I use a stone to hold the tuber down in the gravel, instead of growing them in submerged pots as some gardeners do, so the roots can meander through the gravel and absorb wastes directly as a living water filter.

Native water plants like blue pickerel weed, our wild Iris hexagona, and those teensy floating duckweed plants add diversity and color while purifying the water and offering shade, habitat and food for goldfish and snails.

Elaborate filters and chemicals keep the ecology unbalanced by continuously filtering out the nutrients that the water plants need, while killing beneficial organisms that create ecological balance. The water in my front pond is now 6 years old and still clear, thanks to my water plants, beneficial bacteria and snails.

Let this new pond age for two weeks so the water becomes fully alive and oxygenated. Expect an initial algae bloom as the juvenile ecology gets established and coats the pond sides with an essential carpet of beautiful green algae your fish will later graze on.

Now the fun part: adding the fish! I never use koi because they tend to eat all the plants that are the primary "engines" of a healthy pond ecology. Koi are closely related to the sterile "grass carp" that the State of Florida introduces to clear out canals and lakes choked by invasive vegetation, Instead, I buy goldfish, usually the cheap "feeder" goldfish that are fed live to oscars and other carnivorous fish. Or treat yourself to the fancy fantails and tri-colored goldfish. You'll be amazed at how quickly they grow into sizable fish, adding swirls of graceful color to their transparent world.

Last but not least, ordinary brown pond snails from a fish store are essential scavengers of excess food, algae and fish poop that can otherwise build up as solids. I know indoor aquarium enthusiasts regard them as a nuisance, but they're beneficial here. Snail poop quickly breaks down and helps to complete the recycling of those nutrients that used to foul your pond. Don't buy those huge apple snails, which will likely eat every single water plant.

Resist the urge to feed your fish daily. You'll soon overload the water with uneaten food that decays, sours the water and kills the fish. Let them graze on mosquito and other larvae and on the green algae you want to grow on the sides of your pond as a very effective water cleanser and oxygenator.

Once a week, drop in a few nuggets of dry cat or dog food instead of those expensive fish flakes. As they float and soften, they give the fish something to strike. Since they are a complete animal food, they act as a vitamin, mineral and protein supplement to the fish's main diet of algae and larvae, and they seem less inclined to cloud the water.

No need to change the pond water, ever. But to prevent the buildup of soluble nutrients, use your watering can now and then to bail out some water and treat all your potted plants, indoors and out, to a deep drench of that vitally rich pond water. Rainfall, plus a very slow drip from your garden hose overnight now and then, will keep your pond filled.

John A. Starnes Jr., born in Key West, is an avid organic gardener and rosarian who studies, collects, cultivates and hybridizes roses for Florida. He can be reached at

Agency puts stamp
on greener mower

Speaking of mowers, the 19-inch rechargeable mulching mowers from Black & Decker is the first mower to carry the Environmental Protection Agency's Energy Star mark. That indicates the cordless rechargeable mower meets guidelines for energy efficiency. It costs less than
$10 a year to operate the mower, which makes only half the noise of a gas-powered lawn mower. It has enough run time to cut a third of an acre on a single charge. Suggested retail: $400.

Lawn mowers for 15 military families

Do you know a military family with a loved one serving in the Middle East that needs a new lawn mower? Nominate them in the Mowers for Military Families program. Lawn-Boy and nonprofit Project EverGreen are partnering to give new Lawn-Boy Insight walk-behind mowers to 15 military families. Submit a form, with a 150-word statement, at or Videos welcome! Deadline: May 14.

Paradise hasn't yet been totally paved

As you plant your spring garden, ponder these facts, from the University of Florida: Statewide there are more than a million vegetable gardens. They average 300 square feet, and each garden represents a retail value of $300.

Straw plant pot turns into compost

New at Home Depot: flowers planted in straw pots, made from rice straw, coconut husks and a natural latex adhesive. Plant pot and all in the ground, and the straw pot starts to biodegrade, forming a soil-enriching compost over the next three to six months. An eight-pack — impatiens, marigolds, or petunias — is $9.99.

House-hunting hummingbirds, hear this

Hummingbirds need help finding appropriate materials to build their nests. You can give them a hand and attract more of them to your yard by hanging a Hummer Helper in your garden or near a window. It's a metal grid that holds a pad of natural fibers hummingbirds love to use to build their nests, which are the size of a quarter. The helper is 6 by 10 1/2 inches and 1/8 inch thick. Price: $11.99 for the holder and one pad of fibers; refill pads are $5.99. Order from Songbird Essentials toll-free at 1-800-269-4450, or e-mail to find a retailer.

Compiled by Times Homes and Garden editor Judy Stark.

Sure to make a few fire ants hot

Do you need to eradicate fire ants? Try this, from Bring several large pots of water to a boil, then start pouring the water in a circle two feet out from the nest, working your way in towards the center. This will destroy approximately 60 percent of the fire ant mounds, the Web site says. One caution: It will probably also kill the grass and plants that you dump it on.

Golden ponds 03/28/08 [Last modified: Tuesday, April 1, 2008 3:36pm]
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