Best Answer: Depends on what you want. People are always trying to re-home large fish. You could find a needy goldfish online at www.craigslist.com. These guys ...
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Pond Building Average Costs . A shallow 4' x 6' or 6' x 8' professionally-installed pond, including excavation, liner, filtration system, and simple rock border might cost $2,000 to $3,500. As a DIY project, the same pond might cost $500 to $1,000. Larger ponds, depending on features and equipment, can easily cost $5,000 to $15,000 or more. Whether you plan to go the DIY-route or higher a pro, it's a good idea to spend some time exploring pond options and potential costs. Resources can be found at:
http://costowl.com/home-improvement/landscaping-build-a-pond-cost.html
The initial set up cost for a small goldfish bowl with a goldfish is around $20. The initial set up for freshwater fish in a 20-gallon aquarium costs around $200, while the initial set up costs for a 100-gallon saltwater aquarium costs $2500-$3000.
https://www.costevaluation.com/how-much-do-fish-cost/
Pond Building Average Costs. 1  A shallow 4' x 6' or 6' x 8' professionally-installed pond, including excavation, liner, filtration system, and simple rock border might cost $2,000 to $3,500. 2  Larger ponds, depending on features and equipment, can easily cost $5,000 to $15,000 or more.
http://costowl.com/home-improvement/landscaping-build-a-pond-cost.html
How Much Do Koi Fish Cost? Koi fish range in price from just a couple of dollars to thousands of dollars. The extreme variation in price is due to their size, color, skin luster and lineage. Domestic average quality Koi generally cost $5-$15 a pound. Small 3-4 inch Koi cost around $3, while large foot long Koi cost around $20-$25. Koi imported from Japan that comes from a prestigious lineage can cost from $20-$700 when they are 5-8 inches long, and $50-$1500 when they are around a foot long. Imported Japanese Koi fish can cost up to $300,000. How Much Do Discus Fish Cost? Discus fish cost varies per location, store, the size of fish and the type of Discus fish. The average cost of a small Discus fish is $25-$60, while large Discus fish range in price from $50-$200; generally young or small Discus fish are about 30-50% less than adult Discus fish.
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You could also rent a backhoe yourself or do it the old-fashioned way with shovels and elbow grease. In any case, the amount of labor required is determined by the pond size and shape. Small ponds hold up to 500 gallons of water, while medium ponds are sized between 500 and 1,500 pounds and large ponds hold 1,500 to 3,000+ gallons.
http://costowl.com/home-improvement/landscaping-build-a-pond-cost.html
That said, there are some basic steps that go into the creation of any pond. 1  Excavation: Pong building begins with excavation. A professional with a backhoe can make quick work of this project phase. 2  Liner: Materials used to line a pond include concrete, fiberglass, EPDM rubber, polyethylene, polypropylene, and PVC.
http://costowl.com/home-improvement/landscaping-build-a-pond-cost.html
The time leading up to pond construction, however, can be un-Zen-like, as homeowners fret over the perceived high costs of the project. In reality, a garden or koi pond doesn't have to be a budget-buster. A modestly-sized pond with basic features can cost a few thousand dollars, less if you perform some of the work yourself.
http://costowl.com/home-improvement/landscaping-build-a-pond-cost.html
If we design your pond you will get a 20% discount on Koi purchases. If you prefer to do it yourself, and many people do, we will still provide as much help as possible.
http://www.koifishponds.com/building.htm
a 4-9 inch koi is small so it should cost about $15. there is no average koi usually pond quality (a.k.a. low quality, not as pretty) koi can run for a 3-5 bucks each these are like 3 to 4 at petsmart or petco. from 5 to 6 the prices jump high, to about 10-15 dollars. 7-9 fish are maybe 20-30 dollars however, if you want QUALITY, prettier fish in general, the prices are a lot higher. especially koi imported from japan. these fish can be worth a lot, though. 3-4 runs from 10 dollars to 20 dollars in some cases 4-5 runs from 25-30 dollars each 7 and above are usually individually priced based on the pattern and quality of the koi
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how much money does a small koi cost
A small koi of 3 to 4 inch costs $3. A small 3 to 4 inch koi costs $3.00.