Copper is slightly better but the alu is ok to use. And since you already got it at home go with it.
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If it ain't broke, fix it.
Setup:
Dual Duron 1100 | Voodoo 3 2000 | Addtronics W8500(WTX) | Eheim 1250
| Car radiator | 2 Innovatech WB |
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