Help. My Ember Tetra died.

Hello chums, im relatively new to fishkeeping, been having my 10 gallon planted tank with 5 ember tetras, 6 White mountain minnows, and a few amano shrimp for 4 months now. Ive never had problems before but for the last month and a half every other week one of my ember tetras gets stuck in the sponge filter and will often appear pale. Yesterday I noticed it was especially pale and today I found it dead stuck in the sponge filter. When I removed it its stomach burst open and small white-ish balls poured out. Could this perhaps be eggs or undigested food? They scattered into my flame moss so im hoping it wont be harmful to leave in. Any ideas on what couldve killed it and if I need to remove the white balls? I attached a picture of my poor cracker (His name) and the aforementioned white balls. Thank you for your help.