"So you want to keep fish ? Page 3
My point in recounting the last story is that the chap had not introduced any new fish or plants to introduce the disease but changed the conditions and stressed the fish to the point that they became "under the weather" and subject to the diseases that were already present in thier environment
I must point out at this juncture that I only started keeping coldwater fish this year, having been "into" trops for about 35 years, although not keeping them all that time. When I got the aforementioned fish with white spot, I was not sure what the time cycle for this disease was at cold water temperatures. I went to a large local  aquarist shop and asked. I was informed by the owner that "its the same as tropical" !.
This I found not to be true, so much for "specialists". It would seem from study that at about 62F the life cycle is about 3 weeks, whereas at 75F, it can be as short as 3 days. This means a longer treatment period to ensure eradication. I treated the fish with King British Whitespot Control and Bacteria Control. I had used the Ich control on tropicals before and found it very effective. Another reason is that a local hardware shop (Kings Lynn) sells these products for �1.99p each. How much do you pay!?. Anyway, after the first treatment it was 12 days till the last spot dissapeared and I treated them for a further 10 days,changing 30 % of the water every 4 days when new treatment was due. (12m/l  for the 3 foot tank they are in). The only signs on the fish left now are a few blood streaks in the tail ends and the obvious missing bits that dropped off!.
It is lovely to have them so active at last and coming to hand to feed. When I got them, two had cloudy eyes and I thought they were blind in one eye, but they have cleared perfectly and seem ok. Just goes to show what bad conditions can cause!.
After the last treatment and a 50% water change I replaced the Charcoal in the Fluval  403 filter, which I had removed before treatment. (always remove charcoal from filters before treating tanks with anything but salt, as the charcoal removes chemicals and dyes etc.)
Whilst all this doctoring was going on, I kept strict quarantine rules in force. They fish are kept and were treated in my garage and all buckets , tubes, rags, syringes (for taking water samples and putting treatment into water. BE ACCURATE !) were kept separate from any used in the house where the trops are or the pools in the garden where the other coldwater fish are. Hands were washed after treatments and feeding and well rinsed to remove any soap residuals. All equipt was washed in clean water with a hose jet after use each time and although no
disinfectants were used at all, presto, no cross contamination! Cleanliness is a good thing to get used to if you are keeping any living thing.
Now you can see why I would rather have an internal or external cannister filter, rather difficult to treat water with charcoal in an U/G filter!, still, suppose you could buy another little filter to do it but thats more expense. Now I have to find a good home for the fish as I have nowhere to keep them, the setup in the garage being temporary. I told you I only bought them out of pity! My small outdoor ponds are already stocked and the introduction of large tank bred fish would not be a good idea, so anybody out there give them a good home?, I wont give them away as I think that if you are not willing to pay for them you dont really want them and wont look after them and I have put a lot of effort into healing them and grown "attatched".
You may have seen the previous mention of salt. I keep salt in all the tanks and ponds. A level teaspoon per gallon of water. I wont go any deeper into the subject, but as you are on the net I recommend you to "THE FISH DOC Salt: the fishkeepers standby". Your search engine will find it.
Well, I have really digressed from my initial idea on tips for starting up, but I feel good getting it off my chest and I hope it makes interesting reading. Maybe I have even helped!. I will put some piccies on a link at the top  that may interest you.