that's incorrect, max size for 3/5 is 100%,
4/5 and 5/5 can go up to 130%,
doesn't matter if pink fruit or red fruit, i seem to have better luck with the normal fruit
i have a 3/5 Deputymon at 116%. the pink fruits are best used on the 3/5 and 4/5 digimon. as they can help you attain a bigger size then green or red fruits. but yeah much luck is needed.
the biggest i have seen or heard of a 3/5 is 116%. some people say they have one. some say they have 115%. but i know from experience 3/5 can in-fact get 116%. use pink fruits only when like 95+. or you can conserve and use at only like 98+. but it's harder to get over 95%. if lucky the pink one bring up to and over 100% from 95%.
the different color fruits are actually different. and i can attest to this from playing the game for like 3years. (played 1year of kDMO before gDMO. so like about 3 years.)