It's the cost difference between them though is'nt it?. 1 Iwaki20RZT will cost me £165 in the UK, I could mod two1250 Eheims an run them parallel for under £90!. three of them would surpass the Iwaki for £135!. It's not just the headmod either, it's the triparallel mod too...
Plus no~one has done it before
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