hello everyone,the last days i've seen my tank to be hit by velvet(most probably... itcould be ich though and just don't know **** because i am new) and i am treating my tank with esha oodinex(that's what my lfs gave me for ich).Today i've been reading some articles about velvet and i've come to conclusion that my tank has been hit by velvet and not ich.My fishes symtoms(my cardinal is fine and my dedardinii is only scratching and he is getting close to surface every now and then) is rapid breathing,their body are full of white spots and they don't really like light(i read that this is a velvet sign)...So my question is according to my symptoms do i have velvet? and how is it possible a velvet to show since i've not added and fish for the last 3 months,could stress lead to velvet?Because in the last 2-3 weeks in order to lower my nitrates by a lot i did almost 250 liters water change(not all in once and my tank is 240 liters) ,could this be a factor that "wake up" my velvet and struck my tank?I also used RODI water for my WC and later i've been told that the ph of the RODI water is like 6.5 or something close to this,maybe a drop to ph stressed my fish ?