There is a splendid picture hanging in my living room, with six fish with peony flowers and lotus flowers. Will it affect Feng Shui?

Yes, it matches well. Six, six, six shun, fish has a meaning of more than a year. Peony and lotus are auspicious flowers, and the whole picture is also very beautiful. There are several similar works by famous contemporary painters and painters, which are similar to the one you described. Choosing such calligraphy and painting to hang in the living room will not affect Feng Shui, but it will also be beneficial.