Please help... By now my new aquarium has been running for about a month or so. Yest I did some change in setup and added some gravel, and now i noticed that one of my five Pandas has gone missing :( i tried to check as much as possible to find it but all in vain. If it died beneath the gravel or got trapped somewhere else how serious it is for the water chemistry ? will it contaminate the water?

thanks in advance