Woah has it turned that dark in two months ? That's happened quickly howdark was the tank it was moved to ? Any lights during daytime ?
I'm no expert on the "wwt" as I've never tried it with ay of my jardini mine are usually in a tank with black back , sides and bottom, but people use "wwt" to try and mimic platinum or albino aros that are worth more money as there a rarer fish , basically it aro is kept in a tank with high white shine on back , bottom , and sides sometimes with an intense white light also (its a lot like tanning an Asian aro with tanning lights ) this makes the fish lighten in colour dramatically making it look more platinum to the untrained eye , few of these guys with genuine platinums would spot it a mile of though