my fish(i think have white spot)

Question
hi, i bought a tank a week ago and left it to do what it needs to do for a week, then i introduced 1 royal red dwarf garami, a silver shark and a sucker fish. my tank is a little bit higher and the same width as an xbox 360 as it is next to mine, over the last couple of days, my silver shark has many white dots like spots over it from its head to the dorsal fin on its back, i have read about white spot and i am very worried about this situation as my garami is prone to desiese to start with. also my garami used to swim up and down the tank all day but has settled in and now my shark has started doing it but in a much faster motion as if it nutty, i thought this maybe through the pain or something.i am going to take a water sample to my fish shop tomorrow, but i hope you could tell me something about these spots on my silver shark,  i look forward to your reply, thankyou.

Answer
Hi Samuel
Well....I looked up the dimensions of an Xbox 360, and this is what I got from this site:
http://news.teamxbox.com/xbox/8417/Xbox-360-Physical-Dimensions/
 
"The Xbоx 360 weights 7.7 pounds (3.5 kg) and is:

309 mm wide x 83 mm high x 258 mm deep

12.15 in wide x 3.27 in high x 10.15 in deep"

And, if that's indeed true, your tank is only about 1 1/2-2 gallons.  I would recommend measuring your tank, if you don't have a tape measure handy, a US dollar bill is 6 inches.  Measure the length, width, and height of the tank, and put the numbers in here at this site, it's at the bottom to get a more accurate tank size:

http://www.fishlore.com/ConversionCalculator.htm

So, what I'm getting at, your tank is way too small for all those fish.  The only thing really suitable for it is a betta, or a paradise fish, and maybe the dwarf gourami(but only one of those fish not all 3), but I prefer to recommend to keep one of those fish in at least a 5 gallon tank.  Your silver shark...that could be a bala shark or an id shark, hard to say since stores will give their own name to fish, and same with the sucker fish-both of those have the potential to grow extremely large.

You mentioned the fish acting "nutty", that's most likely the fish suffering from ammonia poisoning.  Real quick, ammonia develops in a tank through fish waste, uneaten food, fish breathing, etc.  A beneficial bacteria develops in a tank that converts the ammonia into nitrites.  Another bacteria develops and converts the nitrites into nitrates.  Ammonia and nitrites are very toxic to fish, often times killing them.  This is what's called the nitrogen cycle or the cycle process.  Here's a link that better explains it:

http://freshaquarium.about.com/cs/biologicalcycle/a/nitrogencycle.htm

Generally all new tanks will go through this process, and tanks that are overstocked with too many fish or too large of fish, the tank never really finishes cycling.  So the ammonia and/or nitrites is always present-slowly killing the fish.  

Now, for the white spot, it does sound like it is ich.  Ich looks like someone sprinkled salt on the fish, small white dots.  Ich is a parasite that will generally infect stressed fish.  Fish in a newly set up tank that's cycling or where there's ammonia present can cause it.  Overcrowding can cause it, sometimes just the move to your tank from the pet store is enough to cause it to show up.  Here's a few articles that explain more of what it is and how to treat it:

http://www.peteducation.com/article.cfm?cls=16&cat=1791&articleid=2421

http://en.wikipedia.org/wiki/Ichthyophthirius

I prefer the salt and heat method for treatment.  But some fish are sensitive to salt, and those fish are also sensitive to a lot of the medications as well.  Without knowing for sure what sucker fish and silver shark you have, I can't really recommend anything specific.  But, most sucker fish are sensitive, so be sure to look for a medication that is made for scaleless or sensitive fish.  

I'm sorry, but I would also recommend that if you're tank is anything smaller then 10 gallons, return at least the silver shark and probably the sucker fish as well-depending on what kind it is.  In fact, even if your tank is 10 gallons, those 2 fish may not be suitable for it.  

Good luck and let me know if you have more questions!

Christy