Don't know what's happening... got a new 33G auarium with 6 guppies, 3 swordfish, 2 mollies,2 barbs and a catfish. 4 mollies, 5 guppies and 1 catfish died 1 by 1 within last couple of weeks. I tested the water, it's fine. Seems like the fish is scratching itself, some get white spots and enlarged red gills right before they die. I put some copperSafe in the tank and increased the temperature to about 27C to kill off the sickness (i think it's Ich) and i wonder if throwing some salt wouldn't hurt as well. If copper and salt can be combined, how mush salt do I need? Is there anyhting else that I can do now?

Hoping, somebody can give a good advice. Thnx :)

Read my section on ick at http://www.fishpondinfo.com/health2.htm#para
I avoid using copper "medications." Many fish don't tolerate this poison well including most catfish. The white spots if they are small (the size of salt grains) would be ick. Scratching is common with ick but could indicate other parasites as well. The red gills may be due to water quality since your tank is new or possibly gill parasites. You tested the water. What were the results? Did you do pH, ammonia, and nitrite?

To treat ick, use a tablespoon of salt per gallon (per 2 gallons if you had any catfish or salt sensitive fish left). I assume you mean swordtails and not swordfish? Guppies, swordtails, and mollies all like a good amount of salt and can always have a tablespoon per gallon. Most barbs don't like salt as much could handle a tablespoon per 2-4 gallons. As I said, I wouldn't and haven't used copper products. I'm not sure if copper and salt together have any additional effects.