The table below shows sizing & pressure ratings, for typical aquarium builds. Using schedule 40 PVC pipe dimensions
| Pipe Size | O.D. | Average I.D. | Minimum Wall | Wt./Ft. | Maximum P.S.I. |
|---|---|---|---|---|---|
| 1/8" | 0.405" | 0.249" | 0.068" | 0.051 | 810 |
| 1/4" | 0.540" | 0.344" | 0.088" | 0.086 | 780 |
| 3/8" | 0.675" | 0.473" | 0.091" | 0.115 | 620 |
| 1/2" | 0.840" | 0.602" | 0.109" | 0.17 | 600 |
| 3/4" | 1.050" | 0.804" | 0.113" | 0.226 | 480 |
| 1" | 1.315" | 1.029" | 0.133" | 0.333 | 450 |
| 1 1/4" | 1.660" | 1.360" | 0.140" | 0.45 | 370 |
| 1 1/2" | 1.900" | 1.590" | 0.145" | 0.537 | 330 |
| 2" | 2.375" | 2.047" | 0.154" | 0.72 | 280 |
| 2 1/2" | 2.875" | 2.445" | 0.203" | 1.136 | 300 |
| 3" | 3.500" | 3.042" | 0.216" | 1.488 | 260 |
| 3 1/2" | 4.000" | 3.521" | 0.226" | 1.789 | 240 |
| 4" | 4.500" | 3.998" | 0.237" | 2.118 | 220 |
| 5" | 5.583" | 5.016" | 0.258" | 2.874 | 190 |
| 6" | 6.625" | 6.031" | 0.280" | 3.733 | 180 |
| 8" | 8.625" | 7.942" | 0.322" | 5.619 | 160 |
| 10" | 10.750" | 9.975" | 0.365" | 7.966 | 140 |
| 12" | 12.750" | 11.889" | 0.406" | 10.534 | 130 |
| 14" | 14.000" | 13.073" | 0.437" | 12.462 | 130 |
| 16" | 16.000" | 14.940" | 0.500" | 16.286 | 130 |
| 18" | 18.000" | 16.809" | 0.562" | 20.587 | 130 |
| 20" | 20.000" | 18.743" | 0.593" | 24.183 | 120 |
| 24" | 24.000" | 22.544" | 0.687" | 33.652 | 120 |