a bloom filter is a structure that is designed to register bit pattern in a way, you can securely say the bit pattern you present to the bloom filter is unique and unknown to the filter if the filter returns that. Unfortunately you cannot invert this phrase: if the bloom filter response marks the bit pattern to be included („known“) to the filter, there is a certain possibility that this is factual wrong.
To get an idea about bloomfilters and how they work have a look here:
and here: https://de.wikipedia.org/wiki/Bloom_filter
and do not miss the great links provided at the end of the articles.
There is a range of bloom filters implemented in go/golang (see https://github.com/search?utf8=✓&q=bloom+filter+language%3AGo&type=Repositories&ref=advsearch&l=Go).
This said i had my own ideas about what is fast in bloom filters and the result is this: