How many goldfish is to many?

Joined
Sep 14, 2018
Messages
728
Reaction score
125
Location
Georgia
Hardiness Zone
8
Country
United States
I have a 725 Gal.pond 2Ft Dp. with 3 waterfalls, 2 bubblers and two canister filters.Also a large UV light.
So how many goldfish will this pond support? Thanks
 
Joined
Oct 28, 2013
Messages
13,070
Reaction score
13,394
Location
Northern IL
Showcase(s):
1
I like this site:


They explain that total water volume is just one factor. The bigger issue is how many fish can your filtration support. UV lights mean nothing in this equation, and waterfalls and bubblers are about the same. Great to have, but if you don't have the appropriate filtration it won't matter.
 
Joined
Sep 14, 2018
Messages
728
Reaction score
125
Location
Georgia
Hardiness Zone
8
Country
United States
These are my filters.
 

Attachments

  • Screenshot_20201125-153401_Amazon Shopping.jpg
    Screenshot_20201125-153401_Amazon Shopping.jpg
    81.3 KB · Views: 64
  • 20201125_152803.jpg
    20201125_152803.jpg
    140.4 KB · Views: 73
  • Screenshot_20201125-155006_Samsung Internet.jpg
    Screenshot_20201125-155006_Samsung Internet.jpg
    58.5 KB · Views: 68
Joined
Jun 29, 2020
Messages
139
Reaction score
83
Location
Buzzards Bay, MA
Hardiness Zone
6b
Country
United States
I know the usual rule of thumb for tropicals is 1 inch of fish per gallon of water. I also know that goldfish are "messy" and produce more waste than tropicals. Following...
 
Joined
Nov 16, 2015
Messages
566
Reaction score
635
Location
Willow Grove,PA
Hardiness Zone
6a/b
Country
United States
Start with a minimum number and be patient because they will multiply. Then let your pond tell you what it can handle. You can test your water and look for signs like increased algae, how the fish are reacting, etc
6 years ago I started with 8 and now have over 60 . I don’t see as many new ones in last two years so I am assuming the fish are keeping the population down
 
Joined
Jun 26, 2016
Messages
31
Reaction score
16
Location
Florida Suncoast
Hardiness Zone
Zone 9b
Country
United States
725 gal. is a good size pond and one thing to keep in mind is that Goldfish will grow bigger in a larger volume of water. We have a 400 gal. pond with a bio filter and a small bog plus two waterfalls with spillways and it supports 8 (large) goldfish and one turtle. If you don't get the heavy monsoon like rains like we have here in Florida, you should pump down and add water, by about about 1/3rd, several times a year.
 
Joined
Oct 28, 2013
Messages
13,070
Reaction score
13,394
Location
Northern IL
Showcase(s):
1
Goldfish will grow bigger in a larger volume of water.

Myth #1 - "fish will grow to the size of their environment". Sure, you can stunt the growth of a fish in a too small container, but healthy fish will grow to the size their genetic make up pre-determines, regardless of the size of the pond. Same as any other animal on the planet.

you should pump down and add water, by about about 1/3rd, several times a year.

Myth #2 - "water changes are necessary to pond keeping". I can tell you that many here - myself included - never do water changes in our ponds. Heavy rains may replace water, but I'd never pump my pond down to replace water intentionally. Pond water matures - the older it gets, the better it is. Adding "new" water can be stressful for your fish and can start a cycle of algae growth that's not desirable. Stability in a pond is the goal. Now if you've been doing water changes and that works for you, great. It's just not commonly promoted in pond keeping as an "absolute must do" like it once was.

The "inch per gallon rule" is another carryover from aquarium keeping. As you can see from the chart I shared, the difference between 30 inches of goldfish and a 30 inch koi is dramatic!
 

addy1

water gardener / gold fish and shubunkins
Moderator
Joined
Jun 23, 2010
Messages
44,340
Reaction score
29,091
Location
Frederick, Maryland
Showcase(s):
1
Hardiness Zone
6b
Country
United States
I do not water changes, except if it rains hard. Never have in the 11 years it has been running, no issues.
My fish have a big pond they have not become huge shubunkins, the biggest is around 10ish inches.
 

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.

Ask a Question

Members online

Forum statistics

Threads
30,782
Messages
508,591
Members
13,043
Latest member
cisifom

Latest Threads

Top