At this time of 12 months, when my highschool science courses are winding down towards summer time trip and room cleanup time turns into necessary, I discover myself going through the drudgery of demonstration aquarium teardown. I at all times attempt to maintain a number of 10-gallon aquariums going always in my classroom to spark curiosity in my college students and to offer specimens of algae and animal microlife for lab investigations. Chief amongst them are my native-species freshwater fish aquarium and a coastal Texas saltwater aquarium, each of which are inclined to have a consistently altering mixture of fish and macroinvertebrates.
When my faculty 12 months begins in late August, my college students are greeted with pretty clear aquariums with fortunately built-in communities of fish and invertebrates. The aquariums draw the scholars like magnets, particularly after they see such oddities as juvenile spider crabs (Libinia dubia), crayfish and diving beetles (Cybister fimbriolata).
Constant State of Change
But because the 12 months wears on, issues start to alter. Mounting duties make it tougher and tougher for me to maintain the aquariums scraped, vacuumed and freshened.
Blue-green Oscillatoria cyanobacters start to blossom within the freshwater aquarium, creeping over the rocks and partitions like a peacock-inexperienced plague. Formerly tiny fish grow to be enormous and hog all the meals for themselves, and supplementing it with smaller aquarium residents. The water develops a inexperienced tint because of the presence of decomposing algae, including to the overall darkening impact of the algal mats.
The saltwater aquarium fares no higher. Instead of cyanobacters, movies of reddish-brown diatoms plate the aquarium furnishings and sides and stain the water a yellowish-brown. Encrustations of salt creep down the edges and spall off onto the ground. My youngsters ask me if there’s something left alive within the aquariums.
“Most certainly!” I reply. Certain species at all times appear to win within the survival contest my aquariums pose. I name these animals “aquarium heroes.” They are literally preadapted to such eutrophicated waters in nature — though you may not comprehend it by their most popular habitats.
My fishy saltwater survivors are: the sheepshead minnow (Cyprinodon variegates), the diamond killifish (Adenica xenica), the Gulf killifish (or what I wish to name the “southern mummichog,” Fundulus grandis) and the fats sleeper (Dormitator maculates). These wonderful and sturdy fish are widespread alongside the Texas Gulf coast in quite a lot of quiet inshore habitats. All prosper in soiled water and develop fats on even the cheaper flake fish meals.
Cyprinodon variegates, F. grandis and A. xenica sport breeding colours in a effectively-lit classroom for many of the 12 months and can spawn readily if given yarn spawning mops, though many of the fry might be eaten within the crowded situations of a 10-gallon aquarium. However, at times I discover just a few centimeter-lengthy F. grandis fry hiding in crannies on the backside once I clear out the aquarium. Fat sleepers are secretive, staying hidden inside shells or behind the filter (I exploit a nook filter) till coaxed out of hiding at feeding time. While shy, their peaceable nature and hardiness make them passion favorites.
Persistent saltwater crustaceans embrace glass shrimp (Paleomonetes pugio and P. vulgaris) and dust crabs, particularly the white-fingered or estuarine mud crab (Rithropanopeus harrisii) and the Texas mud crab (Neopanope texana). The first of those crabs has apparently just lately invaded purely freshwater habitats. Mud crabs keep small, however bigger ones do pose some hazard to fish at night time by catching them whereas they sleep on the underside. They dwell for years in aquariums with essentially the most minimal consideration.
Another invert hero is the warty sea anemone (Bunodosoma cavernata). This powerful anemone wants solely occasional bits of fish and to have the bottom of its column cleaned from time to time to remain expanded and wholesome. Several of my specimens are actually approaching their third 12 months in my aquariums, having survived a number of “transplantations.”
In my freshwater aquariums, three of the strongest heroes are black bullheads (Amieurus melas), Notropis shiners and lake chubsuckers (Erimyzon sucetta). Large black bullheads look nice in exhibition aquariums, however in smaller aquariums they should be eliminated after they attain about 6 inches in size or they are going to eat every thing within the aquarium. In my jap Texas neighborhood, the blackspot shiner (N. atrocaudalis) is a good-looking native “specialty” that I make the principal fish in my faculty freshwater aquarium. This peaceable shiner colleges superbly, at all times eats readily and survives essentially the most punishing aquarium neglect. Other species and even genera of shiners, particularly the blacktail shiner (Cyprinella venusta), are additionally fairly hardy, however many are delicate and require extra exacting care.
I don’t need to give anybody the impression that I wish to maintain soiled aquariums — it simply occurs. If you’re a trainer, you’ll perceive. But for these of you who need to have an aquarium that may comprise dwell recent and saltwater fish so long as it has water in it, aquarium heroes will be the reply!