Mixing metals in wc bad?

[Harbz]

I am currently buying bits for my new WC setup. Purchased a couple of heater cores from ebay, and ehiem pump. The heater core are made from aluminium while cpu blocks are copper. Will this metal mix cause adverse effects?

thanks.

 

[Harbz]

I now have a copper block, 2 aluminium heater cores and a thermochill pa120.3 (copper?). Not sure how much of a dangerous mix this is in terms of corrosion. Should i dump the heater cores and just use the thermochill? Or will anti corrosion addative stop the corrosion?