Like others have mentioned, that pond tubing is absolute garbage.
I use it just for water changes and would never rely on it to plumb a tank.
I think it's the 1.25" TetraPond pond tubing. It has terrible reviews on Amazon.
If you aren't going to hard plumb, Flex PVC is the way to go.
For the record, I'm hating on the product, not on Joseph.
Although, I'm not sure why he said the pond hose was "very, very thick" because it's absolutely not. The sidewall of the tubing (not the ribbing on it, but the actual sidewall) can't be much more than a millimeter.