Open/Male - Short Course - 400m Individual Medley - Aberystwyth and District Swimmin - All Time - Open Age Group
| Rank | Name | Ranked Club | YoB | Meet | Date | Time |
|---|---|---|---|---|---|---|
| 1 | Sam Middleton | Aberystwyth | 89 | West Wales Area Champs, Penlan Swansea | 11/02/06 | 4:42.20 |
| 2 | Joshua Nathanie Harries | Aberystwyth | 92 | West Wales Regional Champs, Penlan | 15/02/07 | 4:49.36 |
| 3 | Steffan Herdman | Aberystwyth | 99 | Swim Wales West Regional Championships, Haverfordwest | 12/02/17 | 4:51.04 |
| 4 | Sion Owen | Aberystwyth | 94 | Llanelli Open Development, Llanelli | 14/03/10 | 5:06.10 |
| 5 | James Payne | Aberystwyth | 01 | Amman Valley Open Meet 2017, Carmarthen | 07/05/17 | 5:07.96 |
| 6 | James Raw | Leic Sharks | 07 | Stockport Metro November SC Open Meet, Grand Central Pools | 16/11/19 | 5:23.55 |
| 7 | Tomos Watson | Aberystwyth | 97 | West Wales Sub Regional Competition, Haverfordwest | 04/12/11 | 5:25.15 |
| 8 | Joseph Gorman | Aberystwyth | 04 | Carmarthen Christmas Open 2019, Carmarthen | 15/12/19 | 5:30.17 |
| 9 | Morgan Evans | Aberystwyth | 01 | Swim Conwy Whitsun Meet, Llandudno | 29/05/16 | 5:34.42 |
| 10 | Benjamin Jones | Aberystwyth | 96 | West Wales Sub Regional, Penlan | 16/11/08 | 5:48.09 |
| 11 | Jude Coleridge | Aberystwyth | 04 | Swim Wales West Region Sub Regional Championships, Haverfordwest | 26/11/17 | 5:59.65 |
| 12 | Jamie Owen | Aberystwyth | 95 | Llanelli Open Development, Llanelli | 14/03/10 | 6:02.13 |
| 13 | Lewis Drakeley | Aberystwyth | 01 | West Wales Sub Regional Competition 2012, Haverfordwest | 25/11/12 | 6:27.53 |
| 14 | James Michael | Aberystwyth | 00 | West Wales Sub Regional Competition, Haverfordwest | 04/12/11 | 6:46.85 |
| 15 | 7:08.87 | |||||
| 16 | Charlie Jones Lewis | Aberystwyth | 06 | Swim Wales West Region Sub Regional Championships, Haverfordwest | 25/11/17 | 7:32.08 |
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