A possible concise summary is:
The speaker is a YouTuber who tries to find interesting things at the bottom of the Bosphorus and the Golden Horn in Istanbul using a powerful magnet. He narrates his adventure and shows his findings, which include a knife, a box, a perfume bottle, a remote control, a lighter, and a bullet. He also encounters some difficulties, such as getting stuck in the middle of the Bosphorus, being stranded on Galatasaray Island, and having to deal with seagulls and dirty water. He also promotes a finance app and makes some jokes along the way.
Here are the key facts extracted from the text:
1. A powerful neodymium magnet was used in the Bosphorus.
2. The magnet can carry a load of about 50 kilos.
3. The magnet does not stick to materials like gold and silver.
4. The Rumeli Lighthouse was built in the 1400s.
5. The Golden Horn has hosted many civilizations.
6. A boat experienced engine trouble due to overheating.
7. Assistance was called to pull the boat out of trouble.
8. Galatasaray Island was visited during the trip.
9. The pool on Galatasaray Island is in a state of disrepair.
10. Various items were found at the bottom of the sea, including a knife and a box.
11. The Golden Horn is connected to the Black Sea by a canal.
12. A strong magnet that can attract about 47 kilos was used for fishing metal objects from the water.
Please let me know if you need any more details or further assistance!