So sorry to hear he didn't make it, its never nice when we lose a fish that we have got attached to I am not 100% sure but I think whitespot need a fish as a host to survive so if you just empty the water out of your biorb and fill it with fresh the bacteria on the ceramic should help speed the cycle up otherwise it would mean starting from scratch if you were to empty the biorb and sterilize it all (a strong salt solution should do) but at least you would be reasured that it was all fresh and cycled for the new additions, good luck
I have given up now with fungus treatments as i think it made my 2 fish i lost worse. I used Interpet no 8 treatment i think-anit fungus anyway and within a day or so of treating the fish they died. I will not be using it again. And i did exactly as the instructions said, i did A Level chemistry so am careful with solutions etc to get them right The only "un-natural" remedy i have is JBL white spot treatment, which turned the water a bit blue when i used it. That seemed quite a gentle treatment and cleared the spot off the orandas tail after 2 days. It said in the instructions improvements should be noticed after 3 days.
I know i go on and on about it but the Supa Aquarium Salt i have has been the best all round cure and for preventing infection. But i noticed you were advised to only use 2 teaspoons of salt, i thought the ratio was more like 1 teaspoon per gallon? maybe thats just for the salt i have
I do suspect that I was the treatments adding to a already stressful environment for my fish... and me being too hasty and adding white spot treatment straight after the anti-fungus as Goldy pointed out...