鱼仅有七秒记忆
[yú jĭn yŏu qī miăo jì yì]
This phrase means 'fish only have seven-second memory.' In popular culture, fish are often depicted as having very short-term memories. People using this as a username might want to imply forgetfulness, living fully in the moment without holding grudges or past issues, much like the perceived state of fish.