DS18B20 doesn’t need lots of power at all, so no need for more.
I have all mine wired for parasitic power. It seems to work the best.
ahh ok I may try that at some point 
how often do you take a reading?
Also my light dimming program seems so stop around a hour short of the set 3 hours. I beleive the time needs to end in L hense the added L in the map fadetimemillis = map(fadetime, 1, 180, 1L, 10800000L);
But I think its that causeing the issue. Is there a better way to write it and add that so that in this part stepWaitTime0 = (fadetimemillis / maxPWM0); stepWaitTime0 would finish with L or could i be lookingat this wrong.
cheers Adam.
The L is symbolic for LONG with Simple/BlynkTimer and AFAIK not actually needed in the timer command, at least for integer sided numbers… perhaps once you get into LONG sizes?? Test and see… But I suspect it might cause issues in your map() command.
I would also recommend serial printing, or something, the resultant map() to see how accurate it is to your needs.
PS you don’t need to include the SimpleTimer library in your sketch, as a variation of it is already included in the Blynk library.
Ok that seems to have resloved that issue now, cheers Gunner. Next issue lol, after around 6 hours, the arduino disconnects from blynk -.- it dosnt reconnect unless i hit the reset button on the ethernet sheild. Is there something im missing in my code for it to try and reconnect?
Cherers
Adam