Learn how Pond Thermometers play an Important Role in the Health of your Pond

Learn how Pond Thermometers play an Important Role in the Health of your Pond

Posted on Apr 9th 2020
Author: Bill Hoffman

“The Importance of your Pond Thermometer”

Hard to believe that such a small thing, like a pond thermometer, can give you so much information throughout the pond season, but it’s true. Read on to find out what the temperature of your pond water actually means and why it is so crucial.


When to Feed and not Feed Your Koi & Pond Fish

Feeding your fish can be a fun family activity, or even a bonding moment with your finned friends - but there comes a time when feeding them can do more harm than good.

  • Your koi fish and other pond fish should ONLY be fed during the season while water temperatures are consistently between 50-80 degrees F.
  • Stop feeding your fish in the fall, before all your pond plants go dormant.
    • This will give the plants time to take up the waste created by the fish and reduce the amount of ammonia built up in the pond and help to reduce the string algae blooms in the spring.
    • The colder the pond water, the less your fish have the ability to metabolize and digest their food. In some cases, undigested, processed food can cause ulcers inside the fish which could lead to death in the spring.
      It’s best to not feed them in cold temperatures.
  • When pond water is 80 degrees F or warmer it is not capable of holding as much dissolved oxygen as cooler water. Oxygen is used by good bacteria to break down fish waste, therefore there is more of a demand for oxygen. That is why we do not feed pond fish at this time. By not feeding them, less waste is created and the present oxygen can be reserved for keeping your fish alive.


Types of Fish Food to Feed your Pond Fish

As water temperatures change, so does the metabolism of your fish. This affects the type of fish food that they need to stay healthy and happy.

  • Cold Weather Fish Food: is higher in fats and contain an easier digestible wheat germ to replace the proteins. This type of fish food should be given to your pond fish when water temps are between 50-70 degrees F.
  • Summer Staple Fish Food: is high in animal protein to promote energy, growth and color enhancement. This type of fish food should be given when water temps are between 70-80 degrees F.
  • Fruits and Greens Fish Food: is a supplemental food good for mixing in with the other types of fish food to add both variety and other nutrients to their food. This mixture has been known to reduce some plant damage done by scavenging koi fish.
  • Variety Mix Fish Food: is a blend of fruits, greens, carbohydrates, protein, wheat germ and vitamins essential to your pond fish. This food will also provide immune support, color enhancements and not cloud the water.


Acclimating New Fish to your Pond or Making Water Changes

For more details read; “How to Acclimate New Koi and other Fish to your Pond

Have you ever touched or pet a fish? That “slime coating” is in fact, part of their immune system. Stressful situations, including drastic changes to the water temperature, will cause them to shed that slime and have adverse reactions. Fish that have been stressed are much more likely to be attacked by parasites or to become ill.

  • It takes approximately 20 minutes for a pond fish to adjust to a 3-5-degree difference in water temps.
  • When doing a water change, or adding large amounts of water into the pond, add the water slowly - so it does not cause shock to the fish.
  • Bringing new fish into your pond requires patience. Acclimating a new fish to your pond will take 20 minutes to an hour depending on many variables, including water temperature.

How Good is your Pond Water Quality?

Clear water does not always mean it is healthy water. High water temperatures are not always controllable and can create havoc on the water quality, unbeknownst to you, when things become unbalanced. Keeping an eye on the water temperature in your pond can explain some fish problems if they arise.

  • As water temperatures rise and fall during a 24-hour period, the pH will also rise and fall.
  • The pH of your pond water holds a direct effect on the concentrations of various toxic elements in the water such as; ammonia, hydrogen sulfide, chlorine and dissolved metals.
  • Small amounts of these elements, in a cooler pond, may not pose a threat, but the rise in water temperatures combined with a rise in the pH has potential to make these variables deadly.

**We recommend keeping a regular record of any water tests performed on your pond water to identify potential problems ahead of time.


When is your Beneficial Bacteria Functional?

There is a plethora of beneficial bacteria and enzymes that break down different kinds of waste and debris within your pond’s eco-system. Some bacteria may come live in a bottle, while others are dry dormant blends of many different types.

  • Most “live in the bottle” strains are not capable of surviving the cold temperatures of winter water. Use these once the water temps reach 55 degrees or higher.
  • “Cold weather blends” will start working as soon as water temperatures are suitable, but also may be used during the regular season. Using a beneficial bacteria, such as Microbe-Lift Autumn/Winter Prep through the winter months will help reduce the amount of algae growth in the spring.
  • Pond Basics Pond Starter Dry Bacteria and Pond Basics Sludge and Muck B-Gone are our most popular and best working blend of beneficial bacteria, enzymes and proteins for your pond. Add this combination of water treatments once a month - from when water temps reach 50 degrees in the spring, to when water temps drop below 50 degrees in the fall.
  • Using Pond Basics Nitrifying Bacteria will help multiply the good bacteria that breaks down fish waste, primarily ammonia.


When can I add Tropical Pond Plants?

Floating pond plants such as hyacinth and water lettuce, have exposed roots that dangle at the water surface. This makes them very susceptible to water temps.

  • Since these plants are originally thought to be native to the Amazon River basin in South America, it makes sense that they need warmer water to survive.
  • Add them to your pond once the water temps are consistently above 65 degrees F.

Some potted tropical pond plants may be added a little sooner, but then night time air temps will come into play according to the plant’s hardiness zone.


There are many aspects that will affect when and what type of pond care is necessary. That is why having and keeping an eye on your pond thermometer is so important – it gives you so much information throughout the different pond seasons.

Shop Pond Thermometers Online.