The RSPCA stated that pets should not be given away as prizes in any part of Wales.
After a petition by Senedd was launched in 2019, the Vale of Glamorgan became fifth of the 22 Welsh councils to ban this practice.
According to the animal welfare charity, goldfish that were given as prizes at fairgrounds could end up living in poor circumstances.
Barry Island Pleasure Park, Vale of Glamorgan's owner, said that the fish at his park are healthy.
Vale of Glamorgan joined Newport, Caerphilly and Wrexham councils in banning pets as prizes.
RSPCA Cymru has urged Welsh councils to take steps to protect animals who may be in poor living conditions due to being given away. RSPCA Cymru launched its #NoFunAtTheFair campaign last January, asking for an end to the practice.
More than 9,000 RSPCA supporters urged their local authorities to prohibit the practice in their area last year.
Fish cannot be given away in England or Wales as prizes to anyone under 16 if they are not accompanied by an adult.
Five councils in Wales have banned or taken action against this practice. 22 councils are in England. The RSPCA encouraged others to follow their lead.
Chris O'Brien, RSPCA Cymru stated: "With Covid restrictions in Wales now completely relaxed, there's an actual risk that the giving out of goldfish prizes will resume in large numbers as funfairs or festivals resume.
"Animal ownership is a huge responsibility. Goldfish should not be purchased in a spur-of the-moment situation.
"Goldfish can be easily stressed, and often, fish that have been won as prizes are subject to shock, oxygen starvation, or die from changes of water temperature. Many may even die before their owners get them home."
Barry Island Pleasure Park owner Henry Danter said that there was no suffering for fish and that people have come back to him to tell him that they have had them for over 20 years.
For more than 100 years, goldfish were given away as prizes at the park. Mr Danter stated that: "Our safety officer would visit the place and check everything. If vendors don't keep the fish to a very high standard, he would have me answer."
"I know concessionaires who make a living from it, and if they are going to ban goldfish at amusement parks, they should also investigate the cruelty in the fishing industry. That makes more sense to my eyes than looking at goldfish as a prize."
Steven Brown, aged 28, works at Maidenhead Aquatics, Cardiff. He said, "Every now, and again, we receive the goldfish with the little bowl they come along at the fair.
"We have had fish that we won at a fair return to us that are unable to swim from the bottom in a tank.
"Most people keep a goldfish in their bowls for five years. But when you tell them that they can live up to 30 years, they don't know what they are talking about."
According to the Welsh Local Government Association (WLGA), "Local authorities in Wales are responsible for ensuring that animals' health and welfare is maintained. They advise owners and businesses, license animal establishments and enforce standards when required."
"The WLGA supports councils by discussing issues in relation to new policies such as these, to ensure that a consistent approach across Wales is taken."
