I'd like to know about creating deep ocean plants that have an alternative to photosynthesis to survive. One sort I'm planning on is similar to the Venus Flytrap because from what I've researched, it can take low sunlight and just survive on bugs. But I'd like to be able to put a large number of thriving plants deep in the ocean of my planet as most of the planet is water and 30% of it is about as deep as the Mariana Trench and the same percentage is even deeper.
Alright so, let me level with you: Nothing really grows at the bottom of the ocean. Even the stuff that looks like plants is really an animal, a type of worm. The reason is what I suspected from the beginning which is that below a certain depth there just isn't enough sunlight for any plants to grow. Below 600 ft (~183 m) there isn't any plant life. At all.
The space is called the euphotic zone (just means sunlight zone) and not only houses roughly 90% of the ocean's wildlife but also all of its plants. So let me speak the ancient words of wisdom we all learnt from Aunty Scripty: you break it, you bought it. The Mariana Trench is way too deep for this to realistically work. Most of what does live within the euphotic zone, however, is algae. So many types of algae.Photosynthesis is the bread and butter of a plants survival, water too, fresh air not so much. Even plants that require lots of shade and little to now sunlight thrive of photosynthesis. Cause what that means is that it needs light. Not necessarily sunlight, just daylight any through a window is enough for most house plants. What I'm saying here is: you can literally decide on anything you want. We don't know about anything else other than photosynthesis to make plants work. What's important though is that whatever you decided on in your story is believable to the reader.
This blog is intended as writing advice only. This blog and its mods are not responsible for accidents, injuries or other consequences of using this advice for real world situations or in any way that said advice was not intended.
https://en.wikipedia.org/wiki/Photic_zone