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5 Tips For Keeping Your Pond And Fish Healthy Through Hot Summer Days

By June 19, 2019March 22nd, 2022Ponds
pond waterfall log

A well-balanced pond is a summertime delight. Playful fish by day, magical lighting by night. Whether you’ve got koi that eat out of the palm of your hand or frogs that sing you to sleep, a pond can be an enjoyable, peaceful, restorative part of your landscape.

But notice we said *well-balanced*. Summertime is notorious for doing some un-balancing, especially as temperatures climb and pond owners take extended vacations away from home without making any contingencies for their aquatic friends.

If you want to keep your pond and its inhabitants healthy all season, then it’s important to head off some of summer’s common problems, and know what to do if a few sneak past you.

pond with waterfall and lilies1. Keep The Oxygen Flowing

A healthy pond requires oxygen. Fish need it to survive, and a lack of it can cause serious health problems. Plus, if your pond is that oxygen-deprived, something is probably wrong with the circulation. And when ponds have circulation problems they can quickly become puddles, which will end up attracting mosquitoes and other undesirable insects.

Since warm water holds much less oxygen than cool water, the oxygen supply in a summertime pond will dwindle naturally. That means you’ll need to take action before it becomes a problem.

Head this one off at the pass by installing an aerator. An aerator will serve you well all year long, keeping water moving and improving oxygen levels. A waterfall is a great natural aerator, but sometimes it’s not enough, especially on very hot days or if you’ve got a larger pond.

If you notice excess algae or if your fish are spending more time at the surface gasping for air, get that water moving before it’s too late.

It’s also a good idea to add submerged oxygenating plants to your pond. These will actually add oxygen to the water in addition to keeping algae at bay, and they’re great cover for fish when it gets too hot to come out and play.

pond fish2. Feed Fish Properly

Overfeeding fish is never a good idea, but it can be especially disruptive during summer months. Excess food sinks to the bottom of the pond where it will decay quickly in the heat. The decaying process is a double whammy: it releases harmful gases like ammonia, and depletes necessary ones like oxygen.

In a pond that may already be low on oxygen, this can be a fatal blow. Avoid this problem by feeding fish appropriately for summer. That means choosing a high-protein food designed specifically for the summer season. This will ensure that fish are getting the right nutrients for their activity levels at this time of year.

Don’t go cheap – low quality food can contain fillers and other non-nutritive ingredients that fish won’t digest as well. All that undigested food will end up as waste that adds to the decaying matter in the pond. And you already know how dangerous that can be.

Feed fish between one and three times daily, no more than they can consume within 3-4 minutes. If you see food floating around or sinking after that, that’s a good sign that you’re overfeeding.

Fish do well on their own, so even if you only feed them once a day, they’ll snack on plants and algae to get the nutrition they need.

And if you’re planning a vacation, consider an automatic programmable feeder. You can set the amount and be assured that your fish will be fed on schedule with just the right quantity to keep them – and your pond – healthy.

pond tall lilies3. Watch The Temperature

A pond in bright sun is a pond in danger of overheating. It’s also ripe for algae blooms. Take stock of how much sun your pond gets. If it’s partially under an overhang, gets shade from nearby trees, or even sits in the shadow of your house, then it will fare better than if it’s placed dead center in the open sun of your yard.

Even a pond that only gets partial sun throughout the day can be in danger of overheating if the temperatures really rise. The best way to protect your pond, and especially fish, is to cover between one-third and one-half of it with surface cover.

Gorgeous plants like waterlilies, lotus and water hyacinths not only look great, but they keep the water cooler and provide protective cover for fish during those brutally hot days.

As an added bonus, plants will naturally consume some of those excess nutrients that algae thrives on. That means fewer (or no) midsummer algae blooms to battle.

But how do you know if water temperature is in the danger zone? Easy – install a simple pond thermometer and keep an eye on it when the weather turns sizzling.

Koi thrive best in water that’s between 68 and 72 degrees Fahrenheit. They can tolerate water that’s hotter, but then they’re at risk of illness and even death. The best way to combat temperature concerns is first to ensure that your pond is deep enough in the first place. Water at the bottom of the pond will be cooler than surface water. Second, keep it shaded so it’s not baking in the sun.

Finally, if you notice a concerning uptick in temperature, consider cooling the pond manually by adding cooler water. But be careful! Adding water can cause harm if done improperly, and that’s our next tip.

pond bamboo edge4. Add Water – Cautiously!

If it’s hot and dry enough, your pond water will evaporate faster than the rain can replenish it. If water levels get too low, your skimmer may stop working, the oxygen will be depleted even further, and your fish are in danger of being crowded.

There may come a time when adding water to your pond – whether to cool it or to replenish it – will become necessary. Before you grab the garden hose and start pumping, stop to understand the potentially dangerous consequences of doing that. Then you’ll be better prepared to do it correctly.

First of all, water out of your garden hose is cold. And if there’s one thing that is deadly to koi, it’s a rapid shift in temperature. The last thing you want to do is start pumping ice cold water into a warm pond.

Secondly, tap water may be safe for human consumption, but it almost certainly contains additives that can be harmful to your pond and fish. That includes chlorine and fluoride. It also contains other minerals that algae love. So you may inadvertently be causing your own bloom and exacerbating the problem.

Your best bet for adding water is to do it through rainwater collection. Prevent all of this by getting set up with a rainwater harvesting system so that you’ll have safer water on hand when you need it.

If you must add water from the tap, do it slowly so that it doesn’t cause a quick temperature change. And add a dechlorinator or water conditioner to combat the effects of other elements. It’s a good idea to consult a professional first so that you’ll know exactly how to replenish the water supply and what you should add to maintain its balance.

Soothing Cascades5. Keep It Clean But Not Too Clean

Your pond needs to be kept clean, but it’s not drinking water! It shouldn’t be cloudy or murky, but it shouldn’t be pristine, either. Some algae is actually good for your pond. It’s a natural food source for fish, consumes excess nitrites and phosphorous, and even produces oxygen.

Unless you’ve got an explosion of string algae covering every surface of every stone, there’s no reason to take a power washer to your pond. In fact, while you can do that for large, algae-covered stones, you should be very cautious if you do. Power washers contain chemical soap residues that can be harmful to your pond and fish.

To keep your pond clean the right way, start by ensuring that you have an appropriately sized filter. If it’s too small, it may not be able to handle the capacity of your pond.

Put a little elbow grease into it and manually skim any floating leaves, grass clippings or debris from the surface. Remove yellowing or dead leaves and dying or dead flowers from plants before they fall into the water. These simple steps will keep excess organic matter from sinking to the bottom of your pond where it will decay, causing all of the problems we mentioned earlier.

Consider consulting a professional to find out if there is something you should be adding to your pond, like beneficial bacteria or a water clarifier.

Maintaining a pond and keeping it healthy throughout the summer is not difficult. It simply requires understanding the natural balance of your pond and taking small, simple steps to prevent problems before they start. And if something does swing out of balance, now you know some key dos and don’ts for bringing it back in line.

If you have questions about pond care, or if you’d like to have a professional come to look at yours, get in touch with us and tell us how we can help. Our pond pros are experienced in creating balanced ecosystems, as well as caring for sick fish and managing pond problems until you’re back to enjoying yours again.