Anyway bout my first reflux still a few days ago, and made my first wash

I'm using dextrose and Samual Willards 48hour yeast.
The instructions on the pack to produce a 25ltr wash is to disolve 7kgs dextrose to 6ltrs of hot water and then top up to 25ltr adjusting the temp to end up at 25c (summertime) or 30c (wintertime)
Now my basic question is: I only had 5kgs dextrose so I only used about 17-18ltrs of water at the right temp, and then added the entire satchel of yeast (235g)
Was this the right thing to do? or should I have used only ~70% of the yeast satchel? or should I still have topped up to 25ltr with water?
Its been sitting in my cellar for a few hours now and is bubbling the airlock every 10-15 seconds or so. Room temp is 22c
Was just a bit confusing with my ratios. Whats the impact on using more or less water in the wash, or more or less yeast and sugar? I mean whats the impact if I only topped up to 10ltrs for example?
Sorry for the long and 'noobie' post!
Thanks
AL