This mirror is being hosted with the permissions of the original content creator for preservation and educational purposes.

Presented by Charles & Linda Raabe
Mactan Island, The Philippines
© 2008 All Rights Reserved

   With the vast variety and just sheer beauty of tropical marine fish available, it can be overwhelming on making a decision as to what species are to be kept. In a fish only system, the options are truly staggering which sadly, leads to many fish mortalitys when we do not understand the needs and compatablity of the various fish familys available to us. As such, I have found it best to go ahead and get your favorite species and then work out from there according to what your aquarium is suited for. Of course, the "favorite" fish should be given the consideration of its needs first. Any other additions will have to have the determination made of compatability with the favored fish and any other additions already made or to be made.
   With coral reef aquariums, it becomes even more interesting to say the least. Not only must we take a fishes needs into account as well as compatability with other fish, we must also determine if a fish species is considered "reef safe" as well, meaning that any fish species that feed on corals or other sessile inverts would not make a good addition to such an aquarium.
   Please do not go into a store or visit an online source and make a purchase without first taking the effort to fully understand a desired species needs. Far to often I hear of horror storys involving deaths of fish due to improper housing and tank mates. I for one enjoy viewing an aquarium that is peacefull and healthy, sitting in front of an aquarium watching a damsel reign terror unto all other tank mates is not my idea of a relaxing and enjoyable way to spend my time. Hopefully the links I am providing will help you in making such decisions a bit easier. I also believe it is important that once a species is decided upon, learning its life style and habitat in nature will better prepare you in understanding its habits and needs.

Photo by Charles Raabe

 Please read the following articles to gain a better understanding of what your fish went through to become your pet.




   The selection of fish species to be kept can be a bit daunting since there are numerous species available to the hobby now. When chosing your pets, please take into consideration each species envrionmental needs, such as swimming room, hiding or sleeping places as well as its dietary needs. Being compatible with others of its own kind as well as with other species is also just as important. Your aqurium's size and its filtration capacity will also determine not only what you can keep, but how many as well. For fish only aquariums, I would employ filtration systems that provide alot of aerobic bacterial living space, such as provided by wet/dry drip filters. For reef aquariums, you will not only be limited to those fish species which are considered "reef safe", but also in the number of fish you will be able to keep and still maintain the low nutrient levels demanded of by corals and invertebrates.

WHAT TO LOOK FOR WHEN PURCHASING A FISH  -  Great tips on how to purchase a healthy fish.

REEF SAFE FISH LIST  - A good listing to give you options for your coral reef aquarium

FISH SELECTION TIPS  -  A listing of hobbyists tips

FISH ACCLIMATION  -  How to acclimate your new pet to its quarantine tank and why.

FISH COMPATABILITY CHART  -  Find out easily which species will get along with other species.

CLOWNFISH AND THEIR HOST ANEMONES  -  Excellent article which matches clownfish species to their host anemone, Please take the time to check out this information.

COWFISH CARE AND IDENTIFICATION  -  An great place to get the information needed when keeping this unique family of fish.

  Since the below listed links provide a great deal of information, I will just touch on what I believe are a few key factors in keeping most marine fish species.

   Feeding :  It is still very common to be told that any of our fish should be fed a single meal each day with enough food put into the tank that the fish can consume within a few minutes. I believe this is yet another carry over from the keeping of freshwater fish, strange as it may sound, but marine fish and freshwater fish are very different in almost every aspect other than the basic fish shape. One very important difference is that marine fish move food through their digestive tracts much faster. This is due to the fact that marine fish spend their entire day picking away at extremely small food items, mostly zooplankton that drifts by in the currents, while some species will also pick off small food prey from the substrates as well. Regardless of wether the food is stationary or drifting by, it is all very small amounts. As such, their digestive systems have evolved to match how much the fish normaly consumes at one time, and being very small amounts, it allows the digestive system to move the food through much faster than their freshwater counterparts. So when we feed the fish one large meal, the majority of that food ends up shooting right out their butts as partialy digested food, meaning that a good deal of that food is not only wasted, since the fish gained nothing from it, but it also adds a significant source of nutrients to fuel algae growth and degrade our waters quality. Since the fish only recieved that one meal, and could only gain a fraction of the nutrition out of it, they are in effect, slowly starving.  Knowing this, I feed my fish very small amounts at one time, and at frequent intervals throughout the day (at least three times) to ensure I am providing their digestive systems with a better suited feeding regime.

   Fish Size :  How many of us have bought a tang or large angelfish species as juveniles and put them into our 40 or 50 gallon aquarium? I know I have, and it was not long before I wished I had not. I of course told myself just as many of you did, that I will get a larger aquarium before the fish gets too large for the aquarium it is in now. Yeah, like that ever happened. Which means I ended up having to either trade the fish in, (always at a loss also) or give it away to someone who had the proper environment for it. While stressing out the fish the entire time. Thankfully, for me, I learned that lesson a long time ago and do not find it hard now to restrain myself from impulse "gotta have that!" purchases or captures. Although I could get away with it now since its only a matter of driving down to the ocean and releasing the fish, I would still rather not have to tear my aquarium's landscape apart just to catch one fish. But the one only real good reason to not do this, is that it simply is not fair to the fish. Yes, I know, they are just "fish", but once we designate something as a pet and not a food item, that designation brings responsibility with it, or at least it should.

   Since it seems that a good many of us do not fully understand the actual differences between saltwater and freshwater fish, and why saltwater fish need to be acclimated to our aquarium's salinity,  yet can go right into either hyposaline (lowered salinity) or a freshwater dip, the below should clarify that there is indeed a great difference between the freshwater and saltwater world.

Saltwater fish

  • These fish are hypotonic to their surroundings. This means their blood has a higher water concentration than the surrounding sea water.
  • As sea water passes through the mouth and over the gill membranes, water molecules diffuse out of the blood into the sea water by osmosis.
  • These fish must replace the water which they constantly lose by osmosis
  • They can also only afford to produce a very small volume of urine.
  • Drinking sea water brings a large quantity of salt into the blood and this has to be removed.
  • To replace the water they lose, saltwater fish drink sea water.
  • To produce a small a volume of urine they must have a low rate of filtration of water into the kidney tubules.
  • This is done by having a kidney with relatively few small glomeruli.
  • Salt is removed by chloride secretory cells in the gills, which actively transport salts from the blood into the surrounding water.

Freshwater fish

  • These fish are hypertonic to their surroundings. This means their blood has a lower water concentration than the surrounding fresh water.
  • As fresh water passes through the mouth and over the gill membranes, water molecules diffuse from the fresh water into the blood by osmosis.
  • These fish must produce a very large volume of urine to balance this large intake of water.
  • This large volume of urine carries salt with it, and the salt has to be replaced.
  • To produce a large volume of urine the fish must remove a large volume of water from the blood by having a high rate of filtration into the kidney tubules.
  • This is done by having a kidney with many large glomeruli - capillary networks from which fluid is filtered at the start of the kidney tubules.
  • Salt replacement is solved by chloride secretory cells in the gills, which actively transport salts from the surrounding water into the blood.

THE NUTRITIONAL VALUE OF LIVE FOODS  -  PART TWO  -  What better way to increase the health of your fish than by providing it will some very nutritional diets.

THE USE OF QUARANTINE TANKS  -  This should be one of your first purchases and used for everything.

FISH CARE GUIDES  -  Basic care information of some of the more popular fish families kept.

FISH PROFILES  -  Detalied care and feeding information on a great number of fish families.

WHAT FISH EAT  -  A good article explaining the dietary needs of fish.

HOW TO CATCH / REMOVE A FISH  -  There will come a time when you will have to do this.

Still not sure of what a specific species needs ? Ask Dr. Frank Marini within his forum which is dedicated to the care and husbandry of marine fish.


FISHBASE.ORG   -  A very large fish index.

Photo Thumbnail pages per common names, click on any photo for more details.
        ( The numbers represent how many thumbnail photos there are per page )
Goby - 1,508    Tangs - 290   Damsels, Clownfish - 1,110   CardinalFish - 665   Dottybacks - 163  
AngelFish - 364   ButterflyFish - 456   Dragonets - 134   FileFish - 183   FrogFish - 104   GoatFish - 214
HawkFish - 112   JawFish - 35   LizardFish - 163   Moorish Idols - 9   Moray Eels - 381   ParrotFish - 556
PipeFish and Seahorses - 259   PorcupineFish - 71   Boxfish / Cowfish - 110   PufferFish - 353
RabbitFish - 101   ScorpionFish / LionFish - 411   Fairy Basslets / Groupers - 1264   ToadFish - 66
TriggerFish - 150   Wrasses - 1,872  

GOBY RESEARCH INSTITUTE  -  From identification, collection and care to breeding information

CLOWNFISH AND THEIR HOST SEA ANEMONES  -  Best resource for such information.

PICTORIAL GUIDE TO FISH DISEASES  -  Finding out what troubles your fish is half the battle, this link also includes treatment plans.

 SPECIES SPECIFIC FORUM TOPICS  -  Kelly Jedlicki's forum discussions concerning a wide range of problems specific to certain species.

Still having trouble identifying a disease or need more information ? Ask Kelly Jedlicki within her forum, which is dedicated to the Disease, Heath and Wellness of marine fish.

THE PRODUCTION AND USE OF LIVE FOOD  -  A very indepth guide on how to culture your own live foods.

PHYTOPLANKTON CULTURING  -  An extremely good "how to" article.

ROTIFERS AND HOME CULTURE  -  A great article on a common fish frys first food item.

THE CULTURE OF CILIATES  -  A very well thought out article.

THE CULTURE OF BRINE SHRIMP  -  A step by step guide and one of the best overall articles I have found.
Additional Brine Shrimp Links -  Hatching Brine Shrimp    DIY Brine Shrimp Hatchery    Growing out Brine Shrimp

THE CULTURE OF COPEPODS  -  A good how to article.

THE CULTURE OF MYSID SHRIMP  -  Great fish food!
Additional Mysid Shrimp Links - Mysids in the Aquarium   Raising Mysid Shrimp  


BREEDING CLOWNFISH  -  An indepth guide to breeding and rearing clownfish.  -  A forum dedicated to the breeding of clownfish species.

Photographic Time Line of Clownfish Egg and Larvae Development  -  Get a close up look at the changes each day brings, a movie is also included.

BREEDING THE BANGGAI CARDINAL FISH  -  A great article on this species care and breeding.

BREEDING THE GREEN WOLF EEL BLENNY -  While neither an eel nor a blenny, this fish is a very interesting species.

BREEDING THE NEON GOBIES  - Great article that can be applied to a great many goby speices.

LARVAL BASE -  An online guide used to indentify fish larvae (fry).

   While often overlooked as a pet, there are a number of eel species that can be kept with suitably compatable fish. Other more large and aggressive species will of course need an aquarium dedicated to them.

A LOOK AT FISH-SAFE EELS  -  A great article which will help in making your species selection.

EEL CARE PROFILES   -  Species specific pages concerning their care.

free web stats

This mirror is being hosted with the permissions of the original content creator for preservation and educational purposes.