The first steps to healthy marine fish

by | Nov 10, 2014 | Science | 0 comments

acclimationclownfishIt’s without a doubt that the process of traveling from a coral reef to a home aquarium is one of the greatest threats to survivability for marine fish, once they enter the reef aquarium trade. Going from a remote island, in the middle of the ocean, across the globe, and arriving in a first world country is wrought with difficulty under the best circumstances. Often, marine fish have spent days on a collection vessel, living in crammed spaces, before being sent to an exporter and beginning their grand journey abroad. For home aquarists, it seems as though we are powerless to smooth this painstaking process. We cannot simply hop on a plane, travel around the world, and personally escort our new aquarium residents to their new home. Just a few oversights during collection can lead to illness, which often doesn’t begin showing symptoms until our new tenants are acclimated into the aquarium environment.

You may be thinking that I am offering a doomsday scenario, a plea of hard truths that should turn anyone away from marine aquariums and have them pursuing more reasonable hobbies, such as crocheting or coin collecting. Actually, the truth is quite the opposite, as I am here to tell you that careful, conscious decisions about where your fish come from and how you handle them, from the moment you open the bag, can have a tremendous effect on the long-term health of your animals. Since online ordering has become popular today, and requires the most diligent acclimation procedures, I am going to focus this post on marine life ordered via the internet.

Where do healthy fish come from?

Unknown-1Most of us have some familiarity with the entire collection process. What many aquarists don’t know is that some locations have a far better record when it comes to providing healthy marine life. Hawaii is one of these locations. In Hawaii, collectors are held to all federal fisheries standards, meaning that they have to comply with regulations, which manage where they can collect, how they can collect, and even determines the quantity of fish allowed per collector. Similar in some ways to rules regarding sport fishing, these state and federal regulations help ensure that the livestock you purchase from Hawaii has been ethically captured, which typically translates to healthy fish, right from the start.

Thanks to Dr. Mac of Pacific East Aquaculture, both the Solomon Islands and French Polynesia have become home to great collection and export stations. Dr. Mac traveled to the Solomons, helping to educate local islanders about coral propagation and net capture of marine fish. Today, the Solomon Islands are a hot bed for healthy fish and corals. Several years ago, Dr. Mac did the same thing for French Polynesia, opening the islands to aquarium collection done right. I’ve personally snatched up various Polynesian clams and fish, and all have been extremely healthy.

I could write a short book of why some locales are better sources of marine livestock, but for the purpose of a this post, I’ll try to keep it simple. Seek out Fiji, Australia, French Polynesia, Palau, Solomon Islands, and Hawaii when possible. The Red Sea has a mixed track record, but my experience has been overwhelmingly positive. Red Sea species are often unique and beautiful, but Red Sea shipments today are a rarity, and command a high price.

Take a long ponder before ordering species collected from the Philippines, and much of the Indian Ocean. I can’t think of a nation that has a worse collection track record then the Philippines, as they were once known for rampant use of cyanide collection. The Indian Ocean is hit or miss, but some species collected there can be found from Fiji and Australia, and are often more colorful when collected from these desirable locations.

Starting on the right foot, without tripping over your feet:

UnknownLog onto any reef forum, and you’ll find as many ways to acclimate fish, as there are to raise the alkalinity in your reef. Float the bag, don’t float the bag; toss in an air stone, don’t toss in an air stone. Proper acclimation is a multi-step process, and in reality, the minute an aquarist cuts open a fish bag, the clock is ticking. It’s in these first moments after a new animal has arrived that many make crucial mistakes that end in tragedy.

As I’ve said many times, a quarantine tank is simply a must have part of the aquarium system as a whole. They cannot simply be set up on the fly, but need to be fully isolated systems complete with proper filtration, lighting, etc. They work best when set up as bare bottomed tanks, with easily moved and manipulated artificial décor. These tanks serve as a place to observe a new arrival, while ushering them into captivity in baby steps, and can even be staging grounds in which to bring two opposing species into peaceful harmony.

Quarantine tanks should have what I call a neutral salinity. Not full salinity, not hypo-salinity, but something around 1.019, which can be manipulated easily if needed. When acclimating fish, many commonly accepted procedures could cause trouble. Often, fish shipped overnight are swimming in an environment that is ripe with ammonia, CO2 and other harmful compounds. Ammonia in a fish bag may not yet be toxic, as it has been sealed from the outside environment. The moment you cut open that bag, chemical processes are making ammonia toxic, and a typical drip acclimation will not dilute ammonia fast enough to prevent it from damaging your new fish’s tissues. Some research suggests that an aquarist has between 15-30 minutes after opening a shipping bag, before ammonia levels begin burning sensitive gill tissue. Fish can survive when subjected to ammonia, but it creates injury, which transforms into another hurdle that must be overcome on the road to successful acclimation.

imagesWhen you open a shipping bag, a good first procedure is to test both specific gravity and temperature. In addition to a neutral salinity, keep your QT tank at a neutral temperature, I recommend 73 degrees F. Most vendors ship their fish in a salinity of about 1.021, and it’s always valuable to ask their shipping salinity, and adjust your QT tank beforehand. Temperature wise, vendors often have a target temperature, meaning that when your fish arrives to you, the temperature should be at, say 75 degrees. Keeping your salinity at 1.019, and temperature at 73 degrees, allows you to quickly lower or raise both parameters to match your fish’s bag water. Allow tank conditions to stabilize, remembering the 15-30 min time frame.

PH is an important factor, as rapid swings cause a great deal of stress. I recommend testing pH, but not until after you’ve made the necessary adjustments. Having good buffers on hand is paramount, in the event you need to quickly raise or lower pH. Typically, I’ve found that pH in shipping bag water is low, so taking steps to keep your QT tank around 7.8 may not be a bad idea. The goal is to make sure your QT tank’s key parameters match those of the bag water. Since you don’t know the bag water’s exact chemistry until the fish arrives, the clock is ticking.

Once you’ve matched water chemistry as closely as possible in the allotted time, release the fish into quarantine.

UnknownTill next time…. As always, if you need help acclimating new arrivals, even those which are delicate and difficult, feel free to send me a line. [email protected]


  • Jeremy Gosnell

    Jeremy Gosnell has been an aquarist for nearly all of his life. While studying sociology in college, he began writing for Freshwater and Marine Aquarium Magazine, moving over to Fish Channel and Aquarium Fish International in 2005. In 2008 he began composing feature articles for Tropical Fish Hobbyist Magazine, and today serves as TFH's monthly saltwater Q&A writer, and is a member of the peer review content editorial board.After becoming a PADI certified dive master and specialty instructor, Jeremy trained with the Beautiful Oceans Academy as a science diver, specializing in coral reef biology, ecosystems and food chain hierarchies. He worked with Beautiful Oceans to promote scientific diving and underwater GPS coral reef mapping and bio-diversity studies for both scientific study and recreational dive charters.He holds various scuba related certifications including PADI master scuba diver, dive master, specialty instructor, DAN dive emergency specialist, marine wildlife injury specialist and several TECH REC technical certifications, including deep water diving, re-breather diving and cave diving.In his spare time Jeremy is a science fiction writer, and his debut novel Neptune's Garden was released in 2010. His second novel is being released later in 2015. Both books are oceanic in nature, exploring the existence of the mythical kingdom of Atlantis, from a scientific viewpoint.

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