I went to Gran Canaria once, Puerto Rico, over 30 years ago, it was the wrong time of year for the Tuna and Marlin and boat fishing seemed to be limited to winching small Tope up from 1800ft 3 at a time, no fun at all. It took about 10 minutes for the lead to hit bottom and 30mins to bring it up!
Had some good sport from the harbour wall though, Stingrays up to about 50lb and various other Bream type fish, plenty of small stuff to be had on float tackle too.
Getting bait was the biggest problem then, we went to a village called Aguenigan from memory and the boats were happy to part with Mackerel etc when they came in. Had some good Bream type fish in the harbour there one evening, to around 10lb on ledgered Mackerel. My mate got a HUGE ray, it completely covered the boot area of the Jeep he'd hired and it took about 2 hours to bring in. The whole village turned out for the spectacle and it was landed by the lights of several of the locals 4x4's. I'd estimate it to have weighed nearly 200lb.
The local kids there were theiving little gits and many small tackle items went missing when our backs were turned.
At that time Puerto Rico was just developing and Aguenigan was all corrugated iron shacks, no doubt it's very different now.