I'd do 20-25%.
Good luck and hope everything goes well.
Wow... daily? How many tanks do you have? If it weren't for the parental limitations... I'd have MTS like mad... but then I wouldn't have very much time for my gf between work and fish keeping. (haha... I just noticed that you said "I'd" rather than just "I," implying that it was a suggestion and not listing what you personally do :silly