Luchi del Mar might be a person known within a specific community or among her followers on Instagram. The fact that she's in a black dress on her IG story could be part of her personal style update, perhaps for an event she attended or just to show off a new look. However, without further information, it's just speculation.
Maybe the black dress she's wearing is a designer piece, which makes it special. Or perhaps the way she posed in the IG story while wearing it is unique.
It depends on the specific H2O concepts. Some concepts are facts. For example, water (H2O) has a unique molecular structure that gives it its well - known properties like high heat capacity. This is a scientific fact. However, some might spread misinformation about H2O, like false claims regarding its ability to cure all diseases when consumed in large amounts, which is clearly fiction.
There were many animes that were similar to Summer Sunshine, such as Summer Sunshine (H2O)'s follow-up, Summer Sunshine Kiss (H2O-CHILI), Summer Sunshine's OVAs and theatres, and Summer Sunshine's manga.
No, H2O itself is not a cause of acid rain. Acid rain is typically caused by the presence of pollutants like sulfur dioxide and nitrogen oxides in the atmosphere.
One common theme is friendship. Fans often explore how Will and Bella's friendship develops over time, especially considering Bella's mermaid secret. It's about their loyalty and how they support each other.
One common theme is the clash of different worlds. Since Percy comes from a world of demigods and H2O is about mermaids and a more aquatic - focused world, there's often a lot of adjustment and misunderstandings as the characters from both universes interact.