Question
First let me say I no longer have fish. 15 Koi/ goldfish died last summer in a matter of weeks. I cleaned the pond and restocked with 2 fish they died also. When I cleaned the pond I noticed worms swimming at the bottom, never saw before last summer. I hope to try one more time this year. My neighbors tree hangs over the pond somewhat. My question is: I want to enlarge the pond I purchased a new liner 20x10 How deep, what length and width can I do w/this liner? Also I would like to shade it w/sailcloth to keep sun and leaves etc. out I would love to get more Koi but at this point am afraid to, how many goldfish and what kind would you suggest? Thank you for your time and help. Faye

Answer
Dear Faye,

Thank you for your question and sorry to hear all fish died.
Also the best wishes for the new year and good luck with the new pondproject.
Starting up a pond can be difficult sometimes.
We need to look at the complete setup including the filter as this is the most important.
I'm not sure how cold it can be in your area, however you need (for koi) at least 1,5 meters of depth.
This means (if your numbers are in feet) the liner should be approx 6 meters x 3 meters.
Therefore I would suggest not to keep koi, only if you can cover the pond to ensure the water not will go under 1癈.
Also, concerning koi I advise maximum 1 large koi per 1000Liters.
So it is up to you to look at the idea.
Koi? I would suggest at least a pond with 10000liters and a depth of 1,5meters.
Other fish, 1,2meters depth.
A good filtration, especially with koi is needed.

Hope this helps out?!
Please do not hesitate to contact me again if you have some questions!

Kind regards,
Raf Segers
Belgium