Totally separate from the house inverter. An off grid system has several main components: inverter to switch ac/dc; charge controllers to regulate charging of batteries; the battery bank itself and the generation sources (diesel, solar, wind, etc).
We did not want to draw from our batteries to run the pool pump (220V x 5amp x 4 hr/d = 4.4 kWh/d)...just way too much.
The solar pump is completely isolated from the house, and runs from the 1500w of solar through its own controller. When we are not using the pump or I shut it down for the winter, we switch the power and divert the 1500 W that normally goes to the controller/pump, to one of our charge controllers and then to the batteries. It is a slick set up, but it needed careful planning to ensure correct voltages from the panels and the pump controller, as well as from the panels to the charge controller. It had the inspector scratching his head a few times! Lol
68,000litre, IG vinyl, LorentzPS 600 Solar Pump & 1/2 HP Tristar, Sandfilter, Aquarite T-15 SWG