Q: Help! How do I get rid of green water?
Linda – Gardnerville, NV
A: Nope, there’s nothing nice about a pea soup-colored pond. Just about every water gardener dreams of a clean, crystal-clear pond – not an algae-filled eyesore. During the warmer seasons, what do you do to prevent and get rid of that unsightly green water? By making sure your pond is in balance.
For a stable pond that inhibits algae growth, you have to strike a perfect balance (or close to perfect, anyway) between fishes, aeration and filtration. And to keep it that way, you have to keep it well maintained. Here’s what you need to know to get rid of that green water.
Watch Fish Load, Feeding
Yes, it’s tempting to take home a dozen or more of those tiny koi from your favorite water garden retailer. But remember: those fish will grow and excrete nutrients that feed the algae. The rule of thumb is to allow 1 inch of adult fish per square foot of surface area, so don’t max out your capacity with one impulse buy at the koi store.
Speaking of fish, take it easy with the food. Feed them a quality diet, like Pond Logic® Growth and Color Fish Food, once a day, and give them only what they can gobble down in a few minutes. Anything more than that just adds excess waste to the pond – which is food for the algae. You can feed your finned friends more often, but be prepared to do more partial water changes or add extra filtration to handle the job.
Add Some Aeration, Bacteria
When you circulate your pond’s water with an aeration system, like the Pond Logic® KoiAir™ Water Garden Aeration System, you deliver oxygen to the bottom where all the muck – a.k.a. algae chow – sits. This oxygen helps all the beneficial bacteria, like Muck Defense® that’s found in the Pond Logic® DefensePAC® Pond Care Package, break down and consume the material there and throughout the water column, resulting in cleaner, clearer water. Plus, the aeration is good for your fish’s health, too.
Filtration – the Bigger, the Better
Go big with your mechanical filtration system. Make sure it’s at least big enough to handle the amount of water in your pond. Manufacturers rate filters for minimal fish load, so if you intend to have a lot of fish, go even bigger.
Plants – floating, submerged, marginals and bog varieties – make excellent natural filtration systems that complement your mechanical and biological filtration. Plants also shade the pond, keeping temperatures cooler and sheltering your fish. So try to cover 40 to 60 percent of your water with plants.
If you still have a pea soup colored pond after getting your fish load right, your feeding routine in check, your aeration system in place and your filtration system humming and growing, it’s time for the big guns – an ultraviolet clarifier. A UV clarifier, like The Pond Guy® PowerUV™ Ultraviolet Clarifier, will help to bind the green water algae so it can be pulled out by your filter.
Keep It Clean, Kind Of
Normal maintenance, like regular partial water changes and debris removal, can go a long way to get rid of excess nutrient buildup. But don’t overdo the filter-cleaning chores. Too much – meaning daily or weekly – washing of the filter media will wear the material down faster and wipe out the beneficial bacteria that actually clean the water. If water is unable to pass through the filter, simply rinse it lightly with water.
And if you don’t already, it’s always a good idea to do an annual spring cleanout of your pond to get rid of organic materials that feed the algae.
Pond Talk: How can you tell when your pond or water garden is out of balance?
Filed under: Aeration - WG, Algae Control, Feeding Fish, Fish Population, UV Filter, Water Gardens & Features, Water Quality Issues Tagged: | Aeration, aquatic plants, bacteria, capacity, clean water, Filtration, fish food, fish load, green water, oxygen, UV Clarifier