I have 4 200 Ah 24v LiFePo batteries with BMS connected in parallel as my house bank in a marine application. The system is currently being charged via a Magnum inverter charger. I am adding 2 550w solar panels 24v connected in parallel to a Victron 150/60 MPPT charge controller. Can I just connect the charge controller directly to the batteries or do I need to add another form of safety protection?
A fuse would help 
I think you will need to connect the solar panels in series, in order to get the MPPT input to 5V above the battery voltage. If the Voc or Vmp of the panels is only 24V, the batteries when fully charged will be about 28V!. Fuse on Mppt battery connection and isolator on the PV connection.
The Voc is 49.95 and the Vmp is 41.97v per panel.
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ok so no problem - your choice of serial or parallel according to shading.
It’s time to connect the charge controller to the 4 24v LFP batteries that are connected in parallel. Do I connect to the #1 battery Pos and the #4 Neg or because it’s parallel can I connect to the Neg and Pos of the #1 battery?
Have a read of wiring unlimited chapter on parallel connection.
You should connect to the #1 battery Pos and the #4 Neg.