That Fish Blog – Aquarium Advice and Information

Hey Fish Bloggers!

Desiree here.

It’s the dead of winter….so invariably my thoughts go to planning my summer vacation.  Some fortunate colleagues of mine have already taken winter retreats to Florida or elsewhere.  But as I pour over maps and travel catalogs, and look at pictures from those friends in Florida, I have realized that you can’t take a fish nerd on vacation. 

It doesn’t matter where you go, the power of “fish nerd-dom” is impossible to overcome in any environment.  I think those of you who fall into this category know what I mean and are laughing hysterically right now.

If you are somehow not in this particular category of nerd – Imagine the last time you went somewhere, anywhere with a real “fish geek”.  In any city we nerds visit there’s ONE question… “Where’s the aquarium?”  We’ll go, not shut up once about anything we see, critique it according to where we’ve worked or visited in prior trips, and then move on to the next one.  Think camping is safe?  NOPE.  Wherever we are, we’re looking for a stream or pond where there are fun rocks to turn over or aquatic plants to identify and more likely than not – all sorts of mundane things (like riffles) to photograph.  OOOH LOOK – A cichlid in a ditch!!! 

And don’t even think of taking a beach trip!  Hobbyists are bad enough, but your trip is hopeless with a “Marine Biologist.”  We’ll instantly revert to stories of field studies, trawling trips, dive sites, and the obligatory drunken college boat trip.  We’ll wax philosophic for what seems like hours on the ramifications of eco-tourism, native fish collection, global warming and garbage vortices, much to the annoyance of those who aren’t quite so passionate about the subjects.

Non fish nerds can’t relate to any of this seemingly insane behavior and are instantly bored out of their minds and think “Here we go again!”  Well, like I’ve told my own non-nerd husband – you’ll have to grin and bear it.  Fish nerds are a passionate bunch and there’s just no way to take a “normal” vacation with any of us.  It’s best just to sit back and enjoy the ride, besides you might just learn something.

 I think New England looks good this year – so many rocky shorelines and tidal pools to fall into!!  Maybe I’ll turn over Plymouth Rock to see what’s under it.  It’ll be great!!

Until Next Time,

Desiree

Melisa here. Well, it is that time of the year again. It’s a bit chilly these days. What better to do than snuggle with the one you love or find someone to love…right?

The Anglers and frogfish that are commonly kept in our aquariums have much less complicated rituals.  Just before mating (usually 8-12 hours before), the females of many common types will begin to fill with eggs, typically 40,000 to 180,000!  Their abdomens become distended, making them quite buoyant.  When the male comes along he nudges the female’s abdomen, stimulating her to move to the surface where spawning occurs.  The eggs are usually released as an egg raft or veil that drifts along for a few days before dropping to the sea floor after the embryos hatch.  Post-planktonic frogfish (1-2 months old) take on the appearance of a perfect tiny Frogfish, but often display bright defensive colors!

Some species actually tend to the eggs, protecting the clutch until they hatch. Lophiocharon trisignatus males attach the egg clusters to their bodies until they hatch.  Some species hold the eggs not only to protect them, but also to lure prey closer with the eggs as a prospective meal for the clueless prey!

Deep sea anglerfish of the superfamily Ceratioidea probably have the most interesting way to find the” love of their life,” to say the least.

When scientists first started studying ceratioid anglerfish they were confused why all they appeared to capture were female anglerfish. It was also noted that most of these anglerfish that were studied had some type of parasite attached to them. It was later revealed that the “parasite” was actually what remained of the male anglerfish. With some further investigation scientists were able to tap into the secret lives of these anglerfish.

At birth the males are programmed to detect scents in the water. They immediately begin their search for a female in the deep dark depths of the ocean. As they mature, the males digestive system shuts down, making the males incapable of feeding themselves. If he does not find a female he will die. Assuming he finds a female he takes a big comp and attaches himself for life. The male anglerfish releases an enzyme that fuses his body with hers. From the moment they are one the male becomes an autotroph living off the female. As time goes by the male begins to degenerate, leaving only lump with is gonads enclosed to release sperm when the female releases her eggs. This extreme mating ritual assures that when the female is ready to release eggs they will be fertilized. 

If you know of any other bazaar mating rituals in the fishy world I would love to hear about them.

Until next time,

Patty

Melissa here. When you think of fish that are swimming around in the ocean, most people think of clownfish and damsels swimming around through the tentacles of anemones with corals and live-rock creating the backdrop of that picture perfect image. Ever wonder what is out beyond the reef? There are many awesome creatures that lurk around in the middle of nowhere, far away from the beautiful reef. One of these awesome fish is the Ocean Sunfish, or Mola Mola. Ocean sunfish are the largest known bony fish, weighing in on average 2,000 lbs for an adult. One of the largest Ocean sunfish ever recorded weighed nearly 5,000 lbs!

Ocean sunfish are usually seen near the surface in open water, swimming upright or on their side soaking up the rays or the sun like a large solar panel. Don’t let their position side fool you into thinking they are sick. It is theorized that they “sun” themselves to warm up from a deep dive. It is known that they also spend a great deal of time below 200 meters. That is quite a ways down.

Ocean sunfish are among the strangest looking fish. The posterior half of their body appears to be cut short. They do not have a caudal fin, instead they have clavus which is an extension of their dorsal and anal fin rays. The fish is laterally compressed, looking like a large oval with a paddle shaped fin on the top and bottom. Their skin is like gritty sandpaper covered in a mucus layer that can be as thick as 5 cm. They are also loaded with internal and external parasites (there is a link at the end if you would like to see the list of parasites that cover the ocean sunfish). Juveniles resemble puffers with their large pectoral fins, a tail fin and body spines that are uncharacteristic of adult sunfish.
Their diet consists mainly of jellyfish, squid, crustaceans, small fish, and lots of zooplankton. As its diet suggests, the Ocean sunfish feed across the ocean depths, from the surface to deeper waters, and in some areas, even the ocean floor. You can only imagine how much food these fish must eat on a daily basis to sustain themselves! They are very difficult to keep for long periods of time in captivity, even in the largest system, so Ocean sunfish are not seen in many public aquariums, but there are a few that have taken on the challenge of keeping them on display. The Kaiyukan Aquarium in Osaka, Japan and The Oceanario in Lisbon, Portugal both have Ocean sunfish on display. In the United States, The Monterey Bay Aquarium is the only one to house a mola mola. The longest known ocean sunfish in captivity made it 10 years. In the wild, they can live 100 years or so. Their growth rate is still undetermined, but a young Mola Mola at the Monteray Bay Aquarium went from a slim 57 lbs to 879 lbs in a mere 15 months. It also sprouted to a height of nearly 1.8m. Fattened up on a diet of squid, fish and prawns, this fish had to be airlifted out by helicopter and released into the bay after outgrowing its tank.
It is generally accepted that ocean sunfish larvae will become millions of times bigger during their life cycle. As you can see, this is definitely not a fish you would find at That Fish Place, but you might come across it while scuba diving, so keep your eye out. Ocean Sunfish are found in both temperate and tropical waters. A lot that remains unknown about the secret lives of ocean sunfish!
Here are some great websites about ocean sunfish: http://oceansunfish.org/ has a fun map showing sightings of ocean sunfish
http://www.earthwindow.com/mola.html has awesome pictures of ocean sunfish.
http://www.oceansunfish.org/lifehistory.html this site has a list of parasites that have been found on ocean sunfish.

Image referenced from Wikipedia.

Patty here. Christmas is a time for giving, as is said, and more than a few out there might be receiving (or giving) something aquarium as a gift this year.  Some will get their very first aquarium kit or bowl, and will anxiously await the time a few days later when they’ll add their first fish and plants to the tank.  It may turn out to be that person’s first taste of what will develop into a life-long passion, hobby or even career. I’m sure that most of you reading this can relate to the experience, getting your first tank, setting it up, getting a second tank for that other type of fish you want to keep, or upgrading to the biggest tank you can fit in your living room. 

Working in the industry and in the hobby, I really find the advances in aquariums and aquarium keeping fascinating.  The technology grows by leaps and bounds each year, and the possibilities are almost endless to what can be housed in aquariums today.  With all the equipment and products available to us today, you have to wonder how it was all started.

An aquarium may be defined as a receptacle consisting of at least one transparent side in which water dwelling plants or animals are kept.  Did you know that people have been keeping fish indoors since Roman times?  The introduction of glass panes around 50 A.D. allowed them to keep sea barbels indoors. The glassed replaced one wall of the marble tanks that contained the fish, allowing them to be viewed with ease.  Fish were also kept by ancient Egyptians and Asians, both as a food source, and for aesthetics.  In the 1300’s large porcelain tubs were produced for keeping and breeding goldfish.  From these early ideas and developments, aquariums evolved in shape and integrity to accommodate the demand.  In the early 1800’s, Dr. Nathaniel Bragshaw Ward developed the Wardian Case, a terrarium that allowed for the successful cultivation and transport of plants.  This was the inspiration for aquariums that we know and love today.  By 1850, not even a decade after the first were produced, these aquariums enabled people to maintain freshwater and marine organisms in stable containment for years at a time.  This hobby popularized quickly in the United Kingdom. In addition to there being ornate, cast iron framed aquaria featured in the Great Exhibition of 1851, the first large public aquarium opened at the London Zoo in 1853, known as the Fish House.

The aquarium hobby exploded after that, spreading across Europe and to the U.S. with aquarist societies, literature, and aquarium advancements fueling the fire.  The interest grew stronger during the Victorian era, when models for society homes were made available, usually constructed of pitch-sealed wood and glass with a slate bottom that could be heated from below.  Native species could be collected and contained easily.

With the introduction of electricity to homes the hobby flourished.  Tanks could be installed in more homes, with artificial lighting, filtration, aeration, and heating.  The boom brought the industry to a boil, gave rise to a demand for exotic fish imports, and allowed it to grow into the phenomenon it is today.  You are one of around 60,000,000 aquarists worldwide and growing.

So whether you’re contemplating your first betta bowl, buying your kid an Eclipse Aquarium kit, or testing the integrity of your floor to see if it will support the weight of a huge new reef tank, know that it’s good to be a part of a hobby so diligently contrived and deeply rooted in history.  We’ve come a long way!

Thanks,

Patty

Hi folks, Brandon here.  I recently re-read my article on the Candiru, and their strange relationship with humans reminded me of another strange relationship between two aquatic creatures.  Some of my favorite marine animals are sea cucumbers, a type of echinoderm related to sea stars and sea urchins.  There are varying types of sea cucumbers, some of which sift through the sand, filtering out organics and leaving sand or silt pellets behind.  Others have fan-like structures that protrude from their mouth that they use to filter small particles out of the water for food.  All sea cucumbers share one characteristic in common; they breathe through their anus using respiratory trees to extract oxygen from the water.  They expand and contract their lower intestinal tract, very similar to how our lungs expand and contract, to take in and expel water.  They can even spray water several feet when exposed to air.   Sea cucumbers are fascinating animals any way you look at them.

Another interesting animal that shares a close bond with certain types of sea cucumbers is the pearlfish.  There are many different species of pearlfish, all of which share the same characteristic long, slender body shape.  Pearlfish seek out shelter from sea cucumbers, but instead of sharing the same hiding place like pistol shrimp and gobies, the pearlfish will actually retreat into the anus of the sea cucumber.  It’s very strange to watch, but amazing nontheless.  The pearlfish will back into the sea cucumbers anus tail first where it is then safe from predators.

It is unclear whether this relationship is commensal or parasitic.  Some pearlfish have been known to nip at the respiratory system of the sea cucumber, but it does not seem to affect the host in any way.  Most sea cucumbers will expel what is known as cuvierian tubes (sections of the respiratory tree) when they are stressed to deter predators from eating the cucumber.  These sections of the respiratory system naturally regenerate over time, so the pearlfish’s nipping does not seem to affect them in any way.

I hope you enjoyed reading about this bizarre but fascinating relationship.

Until next time,

Brandon