Welcome @Jwoosley, thanks for joining us in the Community! 
There is a Delete Record action for Zapier Tables that you could use in a loop to erase the rows before adding new ones with a Create Record action. But I’m a little confused as to why they would need to be erased and re-written each time. What type of data is being stored in the table? You mentioned that a form triggers the Zap, so are you looking to store the information that’s captured by the form into the table but split it out across 25 rows?
You also mentioned that you tried using the Update Record action to update the existing records but it was only updating the first. Was that happening while testing each action within the loop? When testing in the Zap Editor it will only ever process the information from the first item in the loop, but when the Zap is turned on it would run through each table record individually, not just the first one. If you turn the Zap on does it update the rows as hoped?
With wanting to create a new table, is it that you looking to overwrite the existing table with a brand new table? Or are you looking to create a new table each time someone fills out the form that triggers the Zap?
Sorry for my confusion here, but if you can share some further details to help us to better understand the desired workflow we’ll be happy to make some suggestions. Also, any screenshots you can share to help illustrate what you’re looking to do here would be much appreciated. Please remember to remove/hide any private information like names, emails, phone numbers etc. from any screenshots first.
Looking forward to hearing from you!