Documents: Special Interest: Water Gardening:

Purchasing Fish For Your Pond
by Carole Reimer
November 24, 1999

Purchasing fish for your pond is very simple as long as you follow a few basic rules. This article will not involve scientific names, nor will it get into Fish Biology 101. Lets just keep to the basics.

Stocking Ratio: Goldfish: - One fish per 3 square feet of water surface area.
Japanese Koi: - One fish per 25sq.ft of water surface area.

The most important reason for stocking fish in your pond is for mosquito control. This is their "job" and they do it very well. I believe every pond should have fish. The size and dept of your pond will determine what kind of fish you should purchase. If your pond is less than 4 feet deep, your pond is not suitable for JAPANESE KOI. JAPANESE KOI require depth for "up and down" swimming action necessary to maintain good health. They also play havoc with aquatic plants. If you love the Koi, as I do, then it can be very hard to walk away. Try to remember that Koi grow very quickly and can reach a length of 3 feet. Most believe that Koi only grow according to the size of the pond they are kept in... well I'm here to tell you that isn't always the case.

JAPANESE KOI colours are unbeliveable and if that is the only reason you are looking at the Koi, you probably haven't seen the many Goldfish varieties on the market. SHUBUNKINS for example, are very colourful and are well suited for most watergardens. The common Shubunkins are blue, red, orange and black... all on the same fish! Other Subunkins such as the Midnight Blue are a deep purple blue with black. They are georgeous!

BUTTERFLY KOI are a fairly recent introduction to the fish world. Their colours have also improved over the past couple of years. The "metallics" are my favorite. These fish do not appear to be as aggressive as their relatives, the Japanese Koi. We have successfully kept them with plants for over 5 years, without any apparent damage to the plants..including lilies, water hyacinths, water lettuce etc. They also appear to thrive during the summer months in only two-three feet of water instead of the 4ft plus depth required for Japanese Koi.

The common Goldfish and Comets are also very well suited for the average watergarden. They usually are a orange colour but also come in white, black, grey, brown and combinations of these colours.

Fancy Goldfish, such as Lionheads, Japanese Fantails (our friend's favourite.. they call their pair "Fric & Frac") Orandas, etc. are wonderful in the pond, but for the most part they do not like our Canadian winters and prefer to be taken indoors during those months.

Small tub gardens, especially those in full sun all day are NOT suited for Goldfish. The water gets much too warm for them. Some folks have success stocking GUPPIES (a small tropical fish), in their tub gardens.

Fish Diseases:

Main cause of fish disease is STRESS!.... Stress from poor water quality, poor feed, overcrowding and shipping to name a few.

Look for the following signs of stress and disease:

  1. Closed fins
  2. Fish huddled together at the bottom of the pond or aquarium.
  3. Skinny looking.. signs of underfeeding, poor feed but most likely


  4. Open sores or bloody spots and/or streaks If the above signs are observed, my suggestion is to not buy fish from that tank.

The following is a brief description of more common fish diseases:

  1. TAIL ROT: Tattered fins and tail
  2. ICK: "Pin" size white dots on body, tail or fins. Best viewed looking head on.
  3. ANCHOR WORMS: Larger size white threads with red sores.
  4. GILL FLUKES, GILL MITES ETC: Red "bloody" looking gills

These diseases can usually be cured or controlled, but unless you have a quarantine tank AND ARE EXPERIENCED in treating fish diseases, it is not wise to purchase sick fish.. no matter how pretty they are. Fish Remedies can be purchased at a reasonable price but if you have to treat a pond.. that's a lot of gallons which can certainly run into an added expense you hadn't counted on.

We have always suggested ponders purchase their fish from a reputable water garden centre or fish breeder. As most water gardeners do not have a quarantine tank, it is a very good idea to purchase your entire fish stock at one time and from one location. Several customers have lost their pet and/or valuable fish because they couldn't resist adding to their stock. They did not quarantine, but instead, just placed the new fish in their pond with others. Bad idea! Sometimes you're lucky and get away with it, but most fish breeders will tell you... QUARANTINE.. QUARANTINE!!

Any ponder will tell you.. buying fish is a lot of fun and usually very rewarding...the kids, the grandkids and the "big kids" become very attached to these finned friends.. It's very hard not to... everytime you walk towards your pond, they are swimming as fast as they can to meet you. Usually they will eat right out of your hands... no wonder we give them each a name.

Just remember to "look before you buy" and please....don't buy too many!

Happy Water Gardening!!!!!

Specific water gardening problems can be answered by writing
Carole Reimer,
Reimer Waterscapes®

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