Curious running one MPPT through a 2nd MPPT?

[tammons]

I dont plan to do this but was wondering...

Say you have a Renogy 200 watt folding panel with the 20A waterproof MPPT on the back of the panel.
And you plug that into a Bluetti 70s or something like that, that already has an internal 20A MPPT.

I was testing this Renogy suitcase panel the other day and was curious if that causes any problems other than less efficiency.

Thanks