Dithers for the display, you won't need separate target fish since you have a group of geo's. The best target fish are always a member of the same species. And the geos will act as targets for the sev's.
The sevs aren't for breeding....at least I doubt they will be. I am unsure of either sev's gender since they are so small and super reds are notoriously sterile. If I get a viable breeding pair, I would be shocked and incredibly excited.
Problem I have with the geos is that I have a 55 ready and waiting for a breeding pair to take up residence. The pair will likely claim the entire tank as their breeding turf and a third geo would just get destroyed. Plus I only have six and they do best in groups of 4+, so adding a third to the pair will leave me with three in the display and their social hierarchy could lead to a couple of deaths.
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