Some how my heater has been unpluged for around 2 days the temp of the tank is 21c is there any problems i should watch out for and should i just rise the temp with the heater straight to 25 or over the week
Just raise it back up a couple of degrees per day. Shouldn't cause them too much harm if they are still looking as healthy as could be expected - if they don't show initial symptoms of shock then they'll be fine.