Heron deterrant wanted but not netting ??

We are in rural East Northants, Nene Valley area, lots of open water around and the herons !
The pond should look like the first picture but after cutting the reed/iris/rushes back ( a mistake in retrospect) we had to take drastic action after the local bird spotted the goldfish. The stakes and rope seem to keep it away from the edge but this morning it was perched on the back of the chair, just waiting.
I really don't want to use netting as our cats are stupid enough to get entangled in it, they are into everything.
The heron in the background is a plastic one, came with the pond pump from auction ! Hides in the reeds !
I saw this on ebay and wondered if anyone had tried it and did it work ?
10 Piece Pond & Fish Guard Protector Plastic Floating Net Ring Protective Cover | eBay
It's the hexagonal 'spiders web' plastic grid that floats on the surface.
Any other ideas welcomed.
Cheers
Brian.

 

I haven’t tried it, and don’t know anyone who has, but I imagine it would be effective.

 

If I were in that position I think I'd give it a go, it won't break the bank if it doesn't work.

 

This Amazon listing uses the same photo as your eBay link and may be useful for the reviews, many of which are critical, as are those on other Amazon listings. Might be helpfull to be aware of potential pitfalls prior to installation.

https://www.amazon.co.uk/Guard-Barrier-Protector-Floating-Deterrent/dp/B00V3ITLMQ

 

You could try "Humming Wire".

 

We've got a wire fence around the edge of our koi pond. The heron needs to be able to land on something to attack the fish. The heron can't stand around the edge with our wire fencing so we have never had any heron issues, however, a lot of other neighbours have had heron issues.