This post is from the website of a professional pond builder, so we know his goal is to sell ponds!  But his comments come directly from 100's of clients that he built ponds for.  I've removed specific products that he mentioned so this article would have more meaning to our readers (and K.O.I. does not tout any for-profit businesses) - but the link to the original article is at the bottom.  Read the 8 Things by clicking on the title or picture...

1. I wish I would’ve known how much I love it I want to go bigger
About 35% of our business is actually making ponds bigger for clients. Not only if you have more pond, do you have less weeds, but you also have less grass or other plants to water. Though ponds evaporate a little, they use up to 75% less water than the same footprint of lawn! Help with the drought, build a bigger pond!
2. I wish I would’ve known how friendly the fish are, I want more
This common occurrence also results in needing a larger pond. The fish are soooo friendly, eating right out of your hand and even letting people pick them up, that everyone wants more!
3. I wish I would’ve known how many colors of lilies there are
Lilies are the ultimate pond plant. If you have a pond, you must have a water lily. The PROBLEM is, there are dozens of colors of lilies. In order to have room for every color of lily you want, you may need a bigger pond!
4. I wish I would’ve known about floating stepping stones
There are many cool features you can add to a pond, but floating steps are one of the most amazing ones, in my opinion. When you are out in the middle of the pond, surrounded by the clear, clean water, with dozens of fish begging for food, and lilies blooming away, you are transported to another world. It is an experience that once people have, they want in their own yard. So they need a bigger pond.
Are you sensing a theme yet?
5. I wish I would’ve known how much my family loves it
I’ve had many clients tell me that they are so pleased that their wife/husband and kids spend more time with them because they are relaxing by the pond together. It’s pretty cool to hear, and now they need a bigger pond.
6. I wish I would’ve known how big koi get
Koi get HUGE!!! They can easily reach a length of 28″-30″ (K.O.I. comment - they really needs to get better Koi, feed them better and learn to keep better water - cause Koi can grow up to 48", and 1 meter Koi are now very common!  Perhaps this pond builder should become CKK certified so he had more up-to-date information!) with a breadth equivalent to a dinner plate!!! Imagine that swimming around in a little 11′ X 16′ pond. You’re gonna need a bigger pond.
7. I wish I would’ve known about simpler Filtration
I have clients dreaming of the ease of maintenance. No dragging out heavy bags of lava rock that can tear and spill everywhere, or fighting with unwieldy pads full of decaying algae and fish waste. There are simple cleaning routines that don’t even require getting your hands wet, much less dirty. People love it. They want a bigger pond.
8. I wish I would’ve known about dojos and hi-fin banded sharks
After seeing the cool varieties of fish besides koi and goldfish that can live in a pond, people wish they had made their pond bigger so they could put more fish in.

Taken from:  http://theponddigger.com/2016/10/08/9-things-i-wish-i-knew-before-i-buil...