Awful generic cartridges colors (Canon)

Hi

I have been using generic cartridges for over a year in my Canon
S630.All has been fine, colors were great (We don't print anything for
work, just for fun.)
I ran out of cartridges and found out my generic supplier had ran out
of business so i went back on the web and selected another which
prices couldn't be beat.Well now everything comes out either all pink
or all blue depending which cartridge is the fullest.Black printing is
fine (Text).
Are these cartridges definitely doing that? Are generic not all
created equal?
If you can recommend a good online generic supplier for S630
cartridges, that would be great.

Thanks a lot

Patrick
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