A club statement stated the fan "decided it [the spraying of the sauce] would be fun" and revealed the condiment-wielding perpetrator would be prevented from attending home matches until the end of the season.
The fan was one of three to be banned by Bradford, while a further two are facing five-year suspensions pending further information from Thames Valley Police regarding incidents that occurred at the replay, which ended 3-0 in Reading's favour.
Listing the rulings, the club said: "One person at the home game who when asked not to drink alcohol in sight of the pitch and not to stand in one of the vomitories, directed foul and abusive language at stewards and threatened them with serious physical violence (and has previously been the subject of a Football Banning Order) has been banned for five years.
"One supporter at the Reading home game who decided it would be fun to spray tomato ketchup over a steward has been banned until 30th June 2015.
"The person who ran onto the pitch at the home game versus Reading was arrested by the Police for the offence and has been banned by the club for five years.
"The person who was arrested and charged by Thames Valley Police for racial abuse of a Reading player [Gareth McCleary], an incident seen by millions live on BBC One, will be banned from the club for life if found to be guilty.
This type of behaviour is totally unacceptable to everyone within the club and the vast majority of its supporters and has been hugely damaging to the image of the club during a great season where it has previously made headlines for all the right reasons.
"The person who used social media to announce that he planned to take pyrotechnics into the Madejski Stadium and on a targeted search was found to have a pyrotechnic amongst his possessions will be banned for five years. Carrying these devices into any stadium is a serious offence and, for Bradford City fans in particular, can never be justified."
Get the best features, fun and footballing frolics straight to your inbox every week.
Thank you for signing up to Four Four Two. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.