Nature Perfect

Crafting Beautiful Landscapes Throughout
The South Puget Sound Since 2000.

2905 Black Lake Blvd SW, Tumwater WA 98512

Current Hours
Landscape Design & Installation (360) 280-5116
Monday-Friday 8:00-4:00
Saturday and Sunday - Closed

POND Supply Store (360) 412-0309
Monday - Friday 8:00-4:00 | Saturday 10:00-4:00

Protecting Pond Fish During Winter

Protecting Pond Fish During Winter

Pond Fish Care , Pond Maintenance & Care 🕔October 14, 2021

by Kerri Bailey Ke*****@Na***********.net

As fall approaches, it’s time to prepare our ponds for colder weather, and protect our pond fish during winter. Keeping your fish safe and healthy during the winter isn’t too challenging as they go “dormant”, do not need to be fed and don’t do much but hang out on the bottom of the pond. Here are some tips to help you keep your fish thriving until the following spring.  

Fish Habitats and Shelters- provide areas for the fish to hide and feel safe. We can do this strategically done with rocks, fish caves and plants. Rocks can be placed so fish can hide under neath, just make sure it is tall enough that fish don’t scrape themselves on jagged edges. There are also “fish caves” you can purchase if you don’t make your own out of rocks or recycled materials like plastic crates, etc. In the PNW we generally have “mild” and unpredictable weather, allowing for several plants that can survive our winters in an evergreen or semi-evergreen state. These plants may furnish comforting cover for fish- Water Hawthorne- waterlily replacement; Rushes- Blue Rushes, Corkscrew Rushes; Grasses- Sweet Flag, Bowles Golden Grass and Ground Covers- Creeping Jenny, Ajuga.  You can experiment with floating islands, and floating plant protectors with plants in them or attached to floating driftwood, just be aware if we get severe freezing weather these plants may freeze and go dormant.

Fish Caves help protect fish from predators

Protection from Predators- hungry critters may visit your pond day or night looking for a tasty meal. It may be a good idea to have at least 2 forms of protection- netting the pond and some other type of deterrent like decoys, red lights, motion detectors or spike strips. Netting your pond also helps keep leaves and other debris out of your pond. When applying netting, make sure it is secured on the edges with stakes or rocks- careful don’t puncture the liner- and that it is pulled taunt over the water (not hanging in the water, fish may get caught). You can build or purchase frames to attach netting to allow plants to grow tall underneath, especially if you keep it on year-round. Read more about Predator Control click here.

Add decoys and other deterrants to keep predators awayfrom your pond

Reduce Sludge & Debris. Keep your pond tidy and clean from excess sludge and plant debris. Sludge looks like a silty soil that can develop over time created from fish waste, soil runoff and decaying vegetation. When our pond plants die back shedding their leaves and flowers, we can remove the debris that lands into the pond with a long-handled pond net or skimming net for fine material. Also, remove floating plants before they die back, if you don’t, they will freeze and become mushy, falling to the bottom of the pond. This “mush” will slowly break down and eventually create nutrients for algae blooms when the weather warms in spring. Avoid this by removing annual floating plants like Water Hyacinths and Water Lettuce by around Halloween.  

Add bird or pond netting over your pond to capture leaves and keep critters out!

Provide 24/7 Aeration. We typically keep our ponds running 24/7 all year in the PNW. We do not want to  our ponds to completely freeze over and we should maintain at least a 2’ hole for gas exchange. Aerators can be installed to help keep our water fresh and help prevent freezing, during winter months. Make sure the diffusers that provide oxygen are in shallow areas, on the shelves or nearer to the water surface rather than sitting on the bottom. If we aerate the bottom of the pond during winter, we could “super cool” our fish which could lead to excess stress and possibly death. Prevent this by keeping the bottom more stagnant, which creates a warm zone for fish to hang out while they survive dormancy.     

Treating for Illness. As you monitor your fish you will notice their normal behavior vs. abnormal behavior that can help you determine if they have a disease or parasite problem. When fish go dormant they hibernate in a state called “torpor” similar to how birds “sleep” during nighttime. During torpor, which starts in October and lasts through late March / mid- April, fish immune system slows down making them more vulnerable to parasites and potential disease organisms. You can treat as a preventative in early fall and again late spring with Broad Spectrum Disease control. Read more about treating fish here:

Winter pond with snow and evergreen Sweet Flag Grass

Stop in and visit us, we are open year-round and are fully stocked with fish food, beneficial bacteria & sludge reducer water treatments as well as a variety of fish care treatments. If you suspect that your fish is not acting right- scraping on the sides or bottom of the pond, swimming erratically or acting lethargic (not due to dormancy)- they may have issues that needs to be addressed. The only way to know if you have parasites is to do a scrape and look under the microscope. We provide this service if you are interested, please email our Fish Expert at: Ke*****@Na***********.net with your questions and for further information.

 You can also visit to find out more about fish health. We also offer classes here at Nature Perfect Pond Supply Store monthly in spring and summer if you would like to attend an upcoming workshop call the store or email for more details.