Your FC level is fine. Ben's Best Guess CYA chart gives a maximum FC for your CYA of 10 ppm so you're fine up to that level. You can go higher for shocking when necessary, to 20 ppm in Ben's chart.
Technically, having an FC of 7 ppm with 70 ppm has the same amount of active chlorine (hypochlorous acid) as around 0.1 ppm FC with no CYA so it's a much lower amount than found in most indoor pools since they usually do not have CYA and it's far lower than found in chlorinated tap water. The FC level itself is a measure of chlorine capacity or reserve so is mostly relevant if you were to drink the pool water, which you generally do not do (at least not in large quantities).
Richard
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