Until you get the bigger tank, I would do at least 50% daily, yeah. You said he's a big fella, so the waste in the water could build up fast. Water changes in the 10G will be less frequent and a much smaller percent!
The Boy Feesh: Indigo CT, Lavatail CT, Ghost CT, Chicory HM, Redfish VT, Magic DT
The Girl Feesh: Christmas CT, Shine VT, Snowflake CT, Stripes VT, Midnight CT, Grif VT, Tangerine VT, Wraith CT, Amethyst VT, Ice CT, Poe CT, Turquoise II CT