Green Neon (Green Cardinal) tetras are a staple of the planted aquarium hobby, and a favorite choice for iwagumi (stone garden) layouts like this one. They are close relatives of the ever so popular neon tetra as well as the less common (but still very popular) cardinal tetra. Unlike its relatives, the Green Neons have a much dimmer red stripe, weak to the point where the red is often unnoticeable. Because of this, it brings the same radiant blue, with a twist of green, while not bringing the "hot" red color-- this fantastically accents the simple and "cool" layout created by the stone layout and negative space of an iwagumi style aquarium. The color is much more intense than the less popular blue tetra's. In other words, it's a pretty standard pick, because it just works really well-- didn't feel the need to be creative here.
While neon tetras swim around the middle of the tank, these rainbow fish are built as surface dwellers. I imagine them swimming amongst the fronds of taller grass species (Eleocharis vivipara and Vallisnaria nana) which will eventually grow tall enough to reach the surface of the water. They should add visual interest, a bit of "sparkle" to the upper area, and an element not usually found in Iwagumi layouts with just 1 display fish species.
Is a fantastic algae eating fish, munching offensive growths of algae off of plants and rocks, while handling Black Brush Algae and other types that no other fish will eat. In addition to algae eating, their grazing disturbs plant leaves, forcing dead leaves and other debris into the water flow, allowing the filter to pick it up. They're also astute at finding (and eliminating) uneaten food gone unnoticed by other fish-- further aiding in preserving the water quality in the aquarium (by not letting food rot).
While they become lazier and less effective algae eaters as they get older, they remain peaceful community fish throughout their lives, unlike Chinese Algae Eaters or Siamese Flying Fox, which can eventually become aggressive. Their simple silver shade is unobtrusive or offensive, but their speed, energy, and inquisitive behavior make them active and charming display fish in addition to their janitorial duties.
Like other pufferfish, dwarf puffers (pea puffers) are primarily invertebrate hunters, and love shellfish. In the aquarium, they are often used to eliminate pond/pest snails. Many freshwater snails find their way into the aquarium by hatching from eggs stuck to aquarium plants.
Snails are not in any way harmful to other tank members or plants-- in fact, their browsing disturbs plant leaves, and they devour uneaten food, much like the Siamese Algae Eaters. They even eat trace amounts of algae from plants, stones, and glass, and species that dig can oxygenate the substrate, bringing oxygen to plant roots (much like earthworms in a regular garden). Unlike their terrestrial relatives, most pond snails cannot eat aquatic plants. In truth, snails are actually beneficial, and the burrowing MTS (Malysian Trumpet Snail) or colorful Nerite species are often introduced into the tank on purpose. Unfortunate, most typical pond snails are a real eyesore, and in huge numbers, can ruin the atmosphere of the planted display tank. In other words, they'd ugly!
Dwarf Puffers are small and unobtrusive predators that are very proficient at eliminating (or at least controlling) snail populations. Their specialized mouths (like all puffers) allow them to crush the shells of its prey, yanking larger snails out of their shells and crushing smaller ones whole. Puffers as a group have problems getting along with other fish and have various levels of aggression, but dwarf puffers are generally harmless in a tank with similar size or larger fish (outside a few incidents of fin nipping), and are even peaceful towards larger invertebrates such as the Japanese Swamp Shrimp. They also have no problems living in purely fresh water. 2 dwarf pluffers have been employed to eliminate snails as well as control my population of copepods.
Japanese Swamp Shrimp are fantastic browsers/algae eaters, and do a lot more of the grunt work than Siamese Algae Eaters (though they won't touch BBA...). Like the Siamese Algae Eaters, they are also excellent bottom dwellers who disturb foliage and eat uneaten food. Some of the best janitors an aquarium can have, and are also pleasing to look at as well!
hahaha, thanks for the intriguing information about your aquarium fishies :) I can appreciate the display of your green neon tetra and rainbow fish inside your aquarium, adding some interesting color and detail. I don't see any of the aquatic janitors (one of them being a pufferfish lol), but I guess that's a good thing :d