Can I use Quaquaval's "Up-Tempo" Ability to put a card from my hand on the bottom of my deck if I have 6 or more cards in my hand?
No, you cannot. You have to be able to draw a card when using this ability.
Source: Surging Sparks FAQ; TPCi Rules Team (2024-11-07)

Relevant cards

Note: All applicable cards may not be listed below.
SV8_52
SV8_52