I would be be carefull of tilapia in a polluted water.I would not eat their flesh.

If you have eaten frozen or store brought tilapia then they will taste like dirt or have a bland flavor. Personally I would never eat tilapia that was farm raised, I have seen some of the farms, Looks more like a septic tank.

They had a Dirty Jobs show where Mike Rowe was cleaning tilapia "ponds". Looked like he was working at a waste treatment center.

I saw that episode. They actually had a striper/tilapia farm. The fish hatchery had the striped bass at the front where the water flowed in. They fed these stripers high protein fish pellets. The tilapia were in separate tanks DOWNSTREAM from the stripers. The tilapia were fed NOTHING. Figure it out! The tilapia were fed the same thing as the stripers but AFTER the stripers ate it. The tilapia were fed 100% waste that flowed downstream from the striper tanks. I can't speak for all commercially grown tilapia but I know what I saw. I would only eat those I caught from area lakes. I would not hesitate to eat those.

WTH?

Absolutely true. I saw that episode. I'll never eat store bought fish/tilapia. It was not healthy eating I'm sure.

If this was a farm in the US, I assure you anything coming off it for sale to American consumers was inspected and certified as both healthy and nutritious...culture methodologies notwithstanding.

In reality, this production scenario is actually efficient and not only produces a a good product, it helps to make the water either recyclable to the system or cleaner for treatment prior to discharge. It also saves on feed.

For your consideration:

Myth: Tilapia eat poop.

Fact: Tilapia are plant eaters; they do not eat poop, unless they are being starved.

Truth: The rumor that tilapia prefer poop comes from an episode of Dirty Jobs on the Discovery Channel in which the host, Mike Rowe, visited a fish farm that raised hybrid striped bass. Mike unknowingly exposed the cruelty of the farmers, as they starved their tilapia into eating the wastes of the more valuable bass. Some time later, after a public outcry, the farm reported that the tilapia were only being used as "cleaners" and were never intended for human consumption. Still not nice, but whatever.

Other investigations into the tilapia farming practices in Indonesia and China, have reported that it is not uncommon for fish farmers to starve tilapia into eating hog manure. Surprisingly, this practice does not have to be disclosed when the tilapia filets are imported for sale in US grocery stores. This is true of all imported fish. To be safe, you should only eat fish raised in the United States.

By the way, we use the word "starve" loosely to mean "not supplying any legitimate aquatic species food source". Tilapia have very strong strike and graze instincts, and will "nibble" on just about anything that enters their water, including fingers and toes.

Entire article:
https://lakewaytilapia.com/Tilapia_Myths.php