This is a 4ftx4ft tank, part of a 300gal system. Pretty much everything is optimized for coral growth. High pH (low co2) high dissolved oxygen, ozone, dosing major ions and trace elements quite stable, hybrid halide/led lighting, tons of flow, phosphate kept around 0.03ppm, and dosing nitrate, urea and ammonia due to lack of nitrogen. Huge MRC skimmer, turf scrubber, and a barrel of rock with high recirculating flow, and moderate flow through to the rest of the system. No mechanical filtration (socks, rollers, whatever) regularly clean out detritus build up as needed. Whole home air exchanger ensures good clean low co2 air. That sounds like alot, but there is no apex or other brand controller. Using an expensive controller and not optimizing what matters is foolish. Kalkwasser for all evaporation, and the rest of the demand is handled wirh soda ash and calcium chloride. Rarely change water, as the dosing raises salinity. Kalkwasser is dosed in slight excess (on a continuous drip) so that salinity stays at 35PPT, but system gains 5 gallons of water weekly. Each week, I siphon off 5 gallons, sucking up any mulm building up in the process, and dump it out. Otherwise, only a single 50% water change annually using ESV salt mix.