High planing speed

My Capelli CAP25WA walkaround has to go over 22 mph to stay on the step (planing) It has no trimp tabs. What could help to be on planing at a lower speed?
It is powered with the new Yamaha F300 4 stroke off shore.

Trim tabs, and large as possible if you want to optimize low speed planing. Keep in mind they cause drag all the time and more the faster you go. Before you put them on make sure you can get 6000 rpm at wide open. Running at low planing speeds with an over pitched motor will create a lugging situation which you want to avoid. Also to much pitch is not very efficient at lower speeds. Better to have a slightly under pitched prop as it will be turning faster and help you hang on plane.

I agree with PBR... Unfortunately, TRIM TABS are probably in order. The F300 is a heavy engine hanging out back. Add placement of fuel tanks, people, and there is alot of weight probably residing behind the pivot point of the hull to achieve plane speed. Only way is to give some lift to the rear via trim tabs. When running at low speed, make sure you have the engine trimmed down as far as possible. Some engine placements allow for some negative trim at the extreme downwnard trim that drives the thrust downward to some extent and helps to reduce minimum plane speed and hole shot time to plane.

Thanks for the advise, it looks consistent, I will try

It is a good idean to trim negative at low speed, I will try but adding tabs looks heavy technical for me. Regards Pierre