Posted: April 10, 2014, 12:55 p.m. EDT
By D. Patrick Donston
I had the pleasure of sharing an informative conversation with Mary Sweeney. Some of us know her as a well-documented writer, editor and author for many hobbyist publications and books. I respect her knowledge of freshwater fish; most notably her experience with discus.
The best way for tropical fish departments to survive in retail today is to diversify. Of course, we cannot do this without specialty knowledge on care or our clients’ wants and needs for the product.
That’s where we started. I asked Sweeney about clearing up discus myths in hopes we would convince others to supply them in their shops. By doing so, you escalate your collection and flavor to excite hobbyists. Talk about word of mouth advertising.
The myth: discus fish are difficult to keep and should be left to experienced aquarists only.
It is best to look at the source of where you would buy discus. Reputable wholesalers are preferred.
Discus. Patrick Donston
Transshipping your own or purchasing inexpensive product may be compromised.
"Domestic strains from discus specialists are actually quite hardy and can be kept easier than certain types of livebearers, wild tetras or certain dwarf cichlid species,” Sweeney said.
She also stated that purified water and low pH are not necessary, as once believed. She pointed out that breeders are spawning discus in harder water with pH levels greater than 7.0.
"They really are quite versatile and adjust well in clean aquariums,” she said.
She and I believe separate tanks are best, as opposed to full-linked systems. Discus may succumb to disease when exposed to incubated pathogens of variable fish species.
Acclimation is key. Once discus have arrived and are unpacked, I recommend the drip method and quarantine for at least three days. Allowing discus to settle in and feed, while clients observe for disease gives them the best opportunity for success.
Sweeney emphasized that discus are cichlids, thus "tough,” with natural vitality.
"They will thrive in most aquaria, with natural and stable diets,” she said.
No specialized formula foods, such as beef heart, are needed. She believes it is more important to consider stress factors, such as water quality and tank mates first. Discus experts concur they should take precedence as your centerpieces; all other fish should be smaller complements. Provide plenty of foliage (live or artificial), and cover your back and sides (of the aquarium) to calm them.
"Discus are not much different than other tropical cichlids,” Sweeney said.
It comes down to keepers’ husbandry practices. Dirty filters, sponges and gravel beds cause problems.
She recommended changing 25 percent a week, siphoning beds and maintaining filter media monthly.
Activated carbon is not necessary, as it has been well documented that carbon dust may irritate discus epithelial cells and lateral line. Sweeney prefers poly filters or ion resins for organic pollutant removal.
We both agree that discus bond with people. It is best to house your stock at eye level, not in bottom tanks viewed downward. Unlike other schoolers, osphranemids, catfish or certain other cichlids, they will respond to your clients. Believe me; they really do!
Dick Au, renown discus specialist, speaker, judge and author once told me: "There’s never been a better time for discus. Germany, once known as the only superb supply, has now been reconsidered to reach the Far East as well. There are many exciting attributes for discus fans, of which can spread to other hobbyists.”
Teaching your clients about discus is something you can do in your shop as well. Dispute the myths by using a small handout with five to eight basic tips and watch your clients get excited. Diversify your collection and let the discus flow …
References and Further Reading
Au, Dick: Trophy Discus. Cichlid Press. 2007
Au, Dick: Personal conversation. "A-Fish Convention”. Long Island, NY 2010.
Sweeney, Mary E: "Discus Myths and Reality,” Amazona. Nov/Dec 2012.
Sweeney, Mary E: Personal Conversation. March 7, 2014.
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