Welcome to

Alter Ecosystems

Long Island's Pond Design, Installation & Maintenance Specialists

Pond & Waterfall Design

Alter Ecosystems focuses 100% on water features, including ponds, Pondless Waterfalls and fountains. You can trust our 20+ years of experience with your next water feature design and installation. Just fill out our contact form to get started.

Pond Maintenance

We're dedicated to providing our awesome customers with the most professional and comprehensive pond maintenance services available in eastern Long Island, NY. We specialize in pond repair, pond cleaning, seasonal maintenance and more.

Based in Sag Harbor, NY

We serve the Hamptons area of Suffolk County, NY: Manorville, Riverhead, West Hampton, Quogue, East Quogue, Hampton Bays, Suffolk, Southampton, Watermill, Sag Harbor, Bridgehampton, Sagaponack, Springs, Amagansett, Montauk and more.

Tour Some of our Favorite Ponds!

As Featured on the Greg Wittstock, The Pond Guy YouTube Channel & Pondcast

Ecosystem Ponds

An Ecosystem Backyard Pond works with Mother Nature to provide food, shelter and safety to the birds and wildlife that visit your landscape – not to mention the koi, goldfish or other creatures you add to it. These ponds develop complex ecosystems that keep the water clear and healthy, without lots of maintenance.

ecosystem flickr
PCO Edits

Pondless Waterfalls

Do you want to enjoy the sight and sound of water in your yard, but you’re not quite ready for a full-fledged pond? A Pondless Waterfall might be right for you. These cascading waterfalls disappear into an underground basin, making a breathtaking and low-maintenance addition to any space.


Have a spot in your garden leaving you befuddled about what to put there? Maybe it’s a shady spot where grass struggles to grow. Perhaps the soil isn’t the best for nurturing healthy perennials and annuals. Or maybe you’re just interested in attracting a few more birds and butterflies. A fountain might be right for you.


Long Island Pond Contractor and Pond Maintenance

We offer pond installation and pond repair for Manorville, Riverhead, West Hampton, Quogue, East Quogue, Hampton Bays, Suffolk, Southampton, Watermill, Sag Harbor, Bridgehampton, Sagaponack, Springs, Amagansett, Montauk and more.

Our Service Areas Include Most Of Eastern Long Island

Contact us to see how we can design the pond or waterfall of your dreams.

Long Island Pond Installation FAQs

The cost to build a pond, Pondless Waterfall or fountain depends on the size and complexity of the project. A small goldfish pond might cost a few thousand dollars, while larger projects often range in the tens or hundreds of thousands of dollars.

Remember: You’re making an investment into your property that will bring enjoyment for years to come. You can find people willing to install ponds on the cheap, but, well, you get what you pay for. Cheaply built ponds will fall victim to leaks, green water and debris build-up. Poorly built ponds also don’t make safe homes for fish, who need good filtration, aeration and shelter to survive.

Contact us to learn more about our building process and how we can design you the perfect, low-maintenance water feature.

Our Ecosystem Pond Design prioritizes ease of maintenance. Skimmers remove most debris from the pond, biofilters keep water clear and plants keep string algae at bay.

Typical maintenance for an Ecosystem Pond includes adding regular doses of beneficial bacteria – often via an automatic dosing system – and emptying the skimmer basket as needed. Fish, if you choose to add them, do best when fed about once a day during the warm months, but most will do just fine feeding on organisms in the pond for a little while if you’re away from home.

Alter Ecosystems offers a full range of Seasonal Maintenance Plans to make life even easier. Contact us to learn more.

Koi and goldfish are the most common fish for decorative water features, but golden orfes, catfish and high-finned sharks can also thrive in New York ponds. Large fishing ponds and lakes offer even more options.

The best fish for your situation will depend largely on the size and design of your pond. Contact us, and we’ll be happy to help you pick the right finned friends for your water feature.


Our Mission

Alter Ecosystems is NOT a “do it all” landscape company – and that’s just the way we like it.

We dedicate our time solely to building and maintaining beautiful ponds, Pondless Waterfalls and fountainscapes. This focus means we can pay attention to the details that matter.

We are water feature experts with years of experience crafting stunning, distinctive ponds, waterfalls and fountains for Eastern Long Island. Owner/Operator Ed Drohan is one of Long Island’s leading pond installers, with more than 20 years in the business.

Our water features combine nature, function and beauty to create a place where you and your loved ones can relax for years to come.

Master Certified Aquascape Pond Contractor Serving Eastern Long Island, New York

Based In Sag Harbor, Serving The Hamptons & Surrounding Areas Of Suffolk County, NY