Yes. I stayed there for just over a week in 2011. We also visited the aquarium. I thought the hotel was quite good.
Thanks cojo1000. It looks like a nice aquarium. Strangely, I went down a rabbit hole and found it after looking at the fish "Arapaima" whilst researching the Amazon river with my son and apparently there is one or more of these fish at the Manila Ocean Park! https://en.wikipedia.org/wiki/Arapaima
I caught an arapaima in Thailand a number of years ago if ever your in London take your son into Kew Gardens, there's some huge ones in there.
I've not used the hotel but I offered the kids a trip to the aquarium two weekends ago and they turned it down, too grown up for that now, I would have enjoyed it, we've been there twice before but only once when Janna was a little older. The aquarium is expensive as are most of the restaurants around the complex.
There seemed to be a lot going on within the complex as a whole. I recall a firework display and other activities which I didn’t watch or take part in but was aware that they were on at the time. Googling, it looks like they are ongoing? https://www.manilaoceanpark.com/gallery?section=id-17&category=park I also enjoyed the hotel restaurant food.
Some photos of the rooms looks great https://www.google.com/maps/uv?hl=e...hUKEwjB2q3Qg9PmAhWPTsAKHcuMAfcQoiowFXoECAkQBg
I've stayed in H2O a few times. Each time was just for one night before a flight from NAIA. It's over priced. No doubt about that. You are paying for the gimmick of the aquariums in your room. However, I'd recommend it as a one off. Kids or the in-laws will love it. And, of course, it's great on Facebook...... The aquarium lights are switched off at night, so you lose the effect at bedtime. The rooms themselves are nothing special. Decent midrange facilities. The hotel has aquarium rooms and also bay view rooms. Manila Bay isn't exactly a world-class beauty spot, but I preferred the bay view to the aquariums. And Manila Ocean Park is quite good as well. One rung above SeaLife Centres in the UK. There should be a discount for hotel residents, but there wasn't any when I stayed. There is also the regular restaurants (Gerry's Grill, some chicken chain etc) on your doorstep, some overpriced trinket shops and arcade if you need to pass the time.