i have way more than enough funds than required and about 2 weeks ago, a friend put a bit of lump sum into my account -close to 2000cad. i was wondering if i would need to explain it since it doesn't affect my proof of funds
It is always a good idea to explain it in an loe. If you do not have a gift deed from your friend then I would suggest adding a line to your lot which shows that the funds that you have minus the 2000 from your friend is still above the minimum requirement for your case.
Please check the cic website for the funds requirement.