Prophylactic Treatments - Yea or Nay

[Featheryfish]

So, I was reading up on how to quarantine any fish I might acquire in the future, since I'm rather attached to the ones I've got and don't want to contaminate their tank with anything. My new 75 is only around 40% stocked, maybe less if I end up needing to separate the catfish from the tetras, so I'm sure I'll want to add somebody, eventually.

I've noticed that whether or not to use prophylactic treatment for fish or rely on a good environment to support their immune systems is a bit of a hot-button topic for some folks...

As a child, I had an unpleasant experience with treatment-resistant, heat-resistant ich wiping out all my guppies, so I like to lean on the side of caution. Trouble is, I'm not sure which is the side of caution.

I'm leaning towards at least de-worming the fish I have and any future fish, since they're all from who-knows-where and what-not. I've found its a good idea to de-worm my mammalian pets... it seems logical to do the same for my aquatic critters... some sources recommend it heartily, but others sources tell me I'll melt their slime coats right off if I try and then they'll develop every disease under the sun. Preventive treatment for bacterial and fungal infections seems to be even more divisive - some swear up and down by it, others condemn it.

What do y'all do?

 

[Byron]

This is not a good idea. First, stress is the direct cause of 95% of fish disease, including ich. If the fish are not stressed, they can fight it off. Stress weakens their immune system, but the only way to restor that is to remove the stress. Newly acquired fish obviously are under severe stress. Second, adding any medication means more substances getting into the fish's bloodstream and that means more stress, so there is little point.

Provide the new fish with clean water, a tank providing what they "expect" (i.e., never use a bare tank, this is only more severe stress), and leave them alone. If they develop something, water changes often deal with it. If not, then and only then consider medications.

 

[Colin_T]

Deworming fish is the only prophylactic treatment I use and I do it to all new fish while they are in quarantine. Fish should be quarantined for 4 weeks. A lot of deworming products also kill gill flukes so it's a bonus there.

As for treating for bacteria and fungus. Never do that unless they have an actual infection.
Most fish medications contain poisonous substances that are considered safe to use in low levels. However, they should only be used if the fish is sick. Some of the more common ingredients in fish medications include Malachite Green/ Victoria Green (causes cancer), and Formalin/ Formaldehyde (preservative).

You want to try and avoid these chemicals if possible. Salt can be used to treat minor fungal, bacterial and some protozoan infections. Heat can be used to kill whitespot and velvet.

Good water quality, big regular water changes, a clean tank and filter, good food and no stress will help most fish fight off most diseases. It's a bit like people. We are covered in bacteria, yeast, fungus and viruses all the time. Yet we don't normally get sick from them unless we are run down, or unwell. Old people, babies, and people with a weakened immune system are more likely to get sick compared to healthy adults. The same applies to fish and any other animal or plant out there. Keep the organisms healthy by providing them with good clean living conditions, and they can usually fight off most problems without the need for chemicals.