A Newb Woes

[bboorreedd11]

ok for many years now, i have been fish keeping but everytime, my fishes keep dying from disease or some other reasons...the bottom line is, they jus keep dieing even though my ammonia nitrite and nitrate lvls are all good..that is ammonia 0, nitrite 0 and nitrate 10-15 ppm..i have a 20 gall tank with a cycled HOB filter with a bio wheel...my tank is also planted...my few questions are :

1) how to prevent fish diseases?
2) how often to do water changes and by how many percent?
3) do i need to vaccum the gravel to suck up the fish poo or jus lift the water siphon tube in the water?
4) what to do when fish is sick
5) how to check if fishes are healthy at the store.

and finally...

6) what should i do when bringing new fish home?

pls help me as much as possible ..thanks

 

[Corleone]

1) First and foremost, good water quality, which it sounds like you have pegged. A varied suitable diet also helps, as does quarantining new fish (see #6).

2) Lot of variables. 25% weekly is a good starting point. Depending on types of fish, stocking, and tap water, you may need more or you may be able to get away with less.

3) Yes

4) This depends on what's wrong. There's so many different courses of action - whether you should isolate them or treat the whole tank, whether you need to treat at all or just improve water quality, what medications to use, should you adjust the temperature or aeration, etc. A good starting point is to post as much information as you can in the emergency section of the site (tank size, full stock list, detailed symptoms, current water stats, picture if possible - there's a template stickied in that forum to follow).

5) Watch the tank - if there's any dead fish, give them all a pass, since you can never be sure what killed the deader and if it's been there a while it can degrade water quality or grow fungus that can harm other fish. Look for discoloration, abnormal swimming, particularly shimmying (swimming in place). Both of these can be simple stress, which is common in store tanks and newly introduced fish. Also look for gasping at the surface, rapid gill movement, abnormal spots (some cichlids get black marks when they're stressed, again, not as big of a deal), fuzzy or slimy patches, frayed or discolored fins, bent spine, damage around the mouth or gills, swellings, wounds, cloudy eyes, pinecone scales.. If it doesn't look right, don't risk it.


6) Keep them in a separate tank for the first 4-6 weeks. Use filter media from your established tank so the temporary tank is cycled. I use some cheap plastic caves and plants and no substrate, which lets you get a look at their waste (look for discolored or stringy poop). If any problems develop, they can be addressed in the quarantine tank without endangering your existing fish. Worst case scenario, you can't lose anything more than the new additions.

Get dedicated equipment for the quarantine tank. Anything that goes in the water - net, siphon, etc. After use, sterilize equipment with a 10% bleach solution and rinse thoroughly with water and a very large dose of dechlorinator.