1. dump all returns into rock area, especially skimmer. all exit underwater.
2. add a mechanical filter.
3. put a valve on r. return line and loose the extra L. return line.
4. slide the bubble baffle more to the right, just before pump in chamber.
5. if you tilt each seperator plate, the water will flow over it like a ramp, quiet like.
6. if you keep all imput pipes to rear, you will have better access and light options.
7. make a plastic screen sock for pump intake.
8. 6 inch may not be high enough for pump intake chamber, it will suck air if level drops much. all chambers will keep full except that one, all evap will come from there, expect 2-3 gal a day possible, think about taller or larger for that chamber.
you should be able to run this 75% full and still handle pump off drainback.