| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Backstroke | 1:31.44 | ROCS Red-Black Duel | 2025-11-22 |
| 100m Breaststroke | 1:32.04 | ROCS Red-Black Duel | 2025-11-22 |
| 100m Butterfly | 1:45.97 | KBM Qualifier | 2025-05-24 |
| 100m Freestyle | 1:12.18 | KBM Heats & Finals | 2026-02-20 |
| 100m IM | 1:23.50 | ROCS Red-Black Duel | 2025-11-22 |
| 200m Breaststroke | 3:14.73 | KBM Heats & Finals | 2026-02-20 |
| 200m Freestyle | 2:51.90 | Cornwall Snowflake Meet 2025 | 2025-11-07 |
| 200m IM | 3:04.08 | Perth Candy Cane Meet | 2025-12-12 |
| 400m Freestyle | 5:51.48 | KBM Heats & Finals | 2026-02-20 |
| 400m IM | 6:34.25 | KBM Heats & Finals | 2026-02-20 |
| 50m Backstroke | 40.94 | Cornwall Snowflake Meet 2025 | 2025-11-07 |
| 50m Breaststroke | 43.22 | Perth Candy Cane Meet | 2025-12-12 |
| 50m Butterfly | 39.88 | Cornwall Snowflake Meet 2025 | 2025-11-07 |
| 50m Freestyle | 31.83 | KBM Heats & Finals | 2026-02-20 |
| 800m Freestyle | 12:12.85 | KBM Heats & Finals | 2026-02-20 |
de Guzman, Ethan's top personal bests include 100m Backstroke (1:31.44), 100m Breaststroke (1:32.04), 100m Butterfly (1:45.97), 100m Freestyle (1:12.18), 100m IM (1:23.50).
de Guzman, Ethan swims for ROC Swimming.
de Guzman, Ethan has competed in 7 meets.