I like ghost mantis Phyllocrania paradoxa, jeweled flower mantis Creobroter gemmatus and ofc orchid mantis Hymenopus coronatus and hierdula sp blue, dont know much about them i really like their colorful skin. No a huge fan of fish, or amphibians but there are some exceptions like carnivorus piranhas and species that live in the ocean eg giga based morays (obc keeping salt water aquarium requires a lot of effort ) from amphibians i like axolotls, i loce reptiles especially snakes my friend had beauriful corn snake i aslo love lizards like dragon one or geckos
Phyllocrania paradoxa is simply stunning (looks just like a leaf),
Hierodula sp. blue is probably one the best looking mantids out there.
Extremely good taste with the fish.
There are some "freshwater" moray eels (like
Gymnothorax tile), but they (especially
tile) don't really live for long in fresh water and prefer brackish water or seawater, but they also have a tendency to forgive mistakes when it comes to water quality as somewhat euryhaline species (e.g. they tolerate different levels of salinity). Sadly they are caught in estuaries most of the time, which they enter for food, removal of parasites or other reasons and then sold as freshwater moray eels.
Freshwater Moray Eels (wetwebmedia.com)
Then there is
Gymnothorax polyuranodon. There is at least some evidence to suggest that they are catadromous (that means that they live in freshwater as adults and then go into the sea to reproduce, like our eels). Some work with them in captivity shows that they are capable of surviving and substantially growing in freshwater. It's a hypothesis at this point, but there is still far too less knowledge. In the literature it's still recommended to keep them in brackish water and saltwater because they often reject eating in freshwater.
Growth, maximum daily ration and intraspecifíc cohabitation of the moray Gymnothorax polyuranodon (Muraenidae) in a freshwater aquarium (researchgate.net)
There is also another species of "freshwater" moray eels called
Echidna rhodochilus, which is very small. And also
Strophidon sathete, the biggest moray eel (>4m, very slender) in the world which lives in the brackish water of muddy estuaries. It can't see very well and therefore bites blindly when the smell of food is in the water. It can pose a danger for its keeper and it's generally not deemed as suitable for captivity in a private household. Nonetheless, an aquarium service from my country once had them on the stocklist, but the available animals were very small (only 40/50cm). They are difficult to catch because you have to exhume them from the ground.
Strophidon sathete - Aquarium Glaser GmbH
Piranhas generally have a worse reputation than they deserve, but the problem is that they require huge aquariums (100L/animal) and are very shy. They also don't do much (but the feeding is needless to say a spectacle).
My favorites:
When it comes to fish I especially enjoy
Thalassophryne, most of them live in marine habitats, but
T. amazonica lives in freshwater. It's called the "Prehistoric Monster Fish"/"The Monster from Peru" by hobbyists and it has venomous spikes. Its looks are simply beautiful. And it also has a very special structure on the surface of its eggs for maximizing fertilization propability with sperma guiding. Breeding attempts in captivity have until now.
Egg surface structure of the freshwater toadfish Thalassophryne amazonica (Teleostei: Batrachoididae) with information on its distribution and natural habitat (researchgate.net)
I also like pufferfish and polypterids, but I know far too less about them. And I also like
Xenentodon, because it's a needlefish from the freshwater and also freshwater flounders (I have seen them irl). Years ago there was a very good community project for the keeping of predatory fish, but sadly the guy responsible for his completely deleted his work.
