You can try rio hyperflow pump for the Beckett skimmer. As much as eheim may be sufficient, that's because for James's skimmer it's on a mazzei injector. Only one constriction and one air hole in the entire injector design. But that's not the case for Beckett. You need a rly strong pump for it.
No joke. Been there seen that done that. Can try googling for the design of Beckett injector and mazzei injector and you'll get my point.
Anyway agree with carbon dose points the guys raised. Your nitrates increased not solely because of vinegar but lack of oxygen due to you running biopellets initially.
In any case, don't fret. Don't scream. Like I've shared, go get Purigen and dump it in. If you want to balance the ph, dose Kalkwasser without vinegar to balance the ph or act as ph buffer. But first... Check your ph.
Hope this helps
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