18 Essentials Everybody Should Know About Saltwater Fish Disease and Quarantine - Fish Health Ep: 2

Categories: Fish Disease, Fish Health

Last updated: Jan 12, 2024

1. Fish Should Live Longer in Captivity

This may come as a surprise but fish in captivity should, and often do, live much longer than their wild counterparts when properly cared for. The environment in your tank is stable and controlled, with no chance of predation and very little stress. The things that kill most fish naturally are simply non-existent in your aquarium. Proper disease prevention and control are a very critical part of making this a reality.

2. A Large Portion of Imported Fish Don't Make it

This is a sad truth that we as hobbyists are responsible for changing. Fish undergo severe stress and are exposed to a myriad of diseases and parasites through the process of being collected and imported to your local fish store. As responsible aquarists, practicing proper disease prevention and control will help change that trajectory and improve the survival rate of wild-collected fish.

3. Seeing a Fish in the Store Isn't Necessary

While it is a bit contradictory to what you might have heard, it's not always necessary to see your fish in a fish store before buying it. Sourcing your fish higher up in the supply chain before it ever reaches a retail location can reduce the exposure to disease and possible stress. That often means you won't get to lay your eyes on it until it's already in your possession.

Of course, the benefit of buying fish from your local store is being able to see or identify any problems the fish may already have before taking it home. This is most certainly valuable when purchasing from your local fish store but not always a necessity because there are other sources for healthy, wild-collected saltwater fish.

4. Diet is Extremely Important

Diet plays an incredibly important role in the overall health of your fish and just because your fish eats the food you provide, doesn't mean it's getting everything it needs. In fact, as much as 50% of premature fish deaths in aquariums can probably be avoided with better diets.

Many fish have specialized diets or niches they fill in the wild and you need to recreate that in your aquarium. This includes the type of food, the frequency at which its offered, and how its offered.

It starts with researching the fish's natural diet, sourcing similar foods for your tank, and then finding out how and when to feed that food. It should also be realized that you will never find a single food that will suffice for the entire tank with mixed species. Take the time and energy to educate yourself about each of the various fish species you have and offer the diet that meets their nutritional and metabolic needs.

5. The Motion of the Ocean - Flow For Excercise

The ocean is constantly in motion, fish have evolved to thrive in that motion. It only makes sense to recreate that environment in your aquarium if you want your fish to thrive moreover survive. Creating water flow with pumps and wavemakers in your tank is how you challenge your fish to swim harder, expend their energy, and condition their bodies to thrive inside your tank.

The degree to which this applied certainly varies based on the species you have. For example, a dragonet lives amongst the rocks, sheltered from strong currents where a tang is often swimming at great lengths to constantly graze algae. Tangs will benefit from stronger currents and flow compared to a dragonet. This is very much related to diet in that you should take the time to understand the fish's natural habitat in order to successfully create that at home.

6. Fish Can Survive a Long Time With Parasites

Fish naturally survive alongside parasites and these things are not always deadly. In your tank, the same thing can occur in which your fish survives with some kind of parasitic ailment. It is only when some additional stress occurs that your fish starts to become affected physically by that parasite. Practicing proper quarantine and disease control can help you alleviate those problems from occuing in your tank.

7. The End-Stage Means END Stage

In many cases, when you see signs of illness or disease it's just too late in the progression of the disease to save the fish. This is exactly why preventative disease control is so important and even if you don't see signs yet, medicating and quarantining your fish could very well be the difference between short-term and long-term survival.

8. Most Fish Have Parasites

Most wild-collected marine fish carry a parasite from the wild. Upon collection, those fish are then mixed with a myriad of other fish species carrying different diseases and parasites, further increasing the chances of carrying disease and parasites into your tank.

9. As it Pertains to Pets, "Cheaper" is Rarely Cheaper

Quarantine and disease prevention is never cheap and certainly increases the initial investment in each fish. However, an unquarantined fish that dies and is replaced multiple times or worse yet, brings disease into your display tank and wipes out the entire tank is certainly more expensive.

10. Eating Habits Matter

While we are often told that a fish that doesn't eat is sick, this isn't always true. A fish that doesn't eat is stressed, but may not be carrying parasites or infected with a disease. Stress cause by aggression, transit, overcrowding, or lack of sufficient habitat can have an effect on a fish's eating habits just the same as parasites or disease.

11. Always Quarantine Fish In Some Way

Why risk bringing disease into your aquarium when you have the ability to prevent it with a quarantine tank? It's just not worth it. You have to assume that ALL fish have been exposed to diseases and many of them will harbor or carry those diseases into your tank. Even if the fish looks and acts fine, quarantine and medication is the only way to be sure.

12. Stress Events Push "Healthy" Fish Over The Edge

Stress can cause a previously healthy fish to succumb to parasites or diseases in your tank. Whether the fish had always carried that disease or was exposed to it from a tankmate, the outcome is the same. Stress can often be the one thing that pushes a previously "healthy-looking" fish over the edge. With proper quarantine and disease prevention, you can reduce the chances of that outcome when your tank inevitably experiences some kind of stress event.

13. Assume All Fish are Infected

Sort of a repeated theme but you have to assume that all new fish are infected with some kind of disease or parasite. The chances or so extremely low that new fish won't carry disease and if you are lucky enough that your new fish doesn't introduce a parasite or disease into your display, the next one probably will. The only way to prevent the spread or stop the cycle is through quarantine and medication.

14. Non-parasitic Issues

There are other problems fish encounter during import that are not related to disease or parasites. Exhaustion and emaciation are just as likely to be causes of poor fish health.

15. Sometimes it's Best to Just Let it Be

Sometimes trying to intervene right away can be problematic and further stress out a fish even further, especially in the case of stress. Sometimes letting a fish settle for a few days is the best approach.

16. Use Isolation Boxes

Isolating new fish inside your display aquarium upon introduction is an incredibly effective practice for successful integration into an existing population of fish. The isolation box should be clear and contain a hide or piece of structure for the isolated fish to feel comfortable. After 2-4 weeks of isolation in the display, the existing fish become accustomed to the newcomer and when you finally release the new fish, aggression is far less likely to occur.

17. Consider a Fish's Natural Habitat

Natural habitats are important for helping the fish feel comfortable. Different fish come from different habitats and live in different areas of the ocean so recreating that habitat in your tank will ultimately help them thrive in your tank.