Mark's Pool Care is an owner-operated, water-chemistry-certified pool service in Santee based on Collinwood Drive, providing weekly maintenance to residential pools in Santee, Lakeside, and El Cajon. The solo-operator model assigns the same technician to every visit, maintaining consistent chemical baselines and catching early signs of equipment wear — including wood-destroying organism damage to pool-adjacent decking that Eliminite Termite Services on Wheatlands Avenue treats with non-fumigation methods. Service visits cover skimming, brushing, tile-line scrubbing, basket clearing, backwashing or cartridge rinsing, and full chemical balancing across pH, alkalinity, calcium hardness, and cyanuric acid levels. Preventive equipment checks on each route stop monitor pump prime, filter pressure differential, and heater ignition sequences, catching small issues before they escalate — the same proactive maintenance philosophy that Liberty Tree Services on Goyette Place applies to canopy management above pool zones. Chemical dosing protocols maintain free chlorine between 1.0 and 3.0 ppm, cyanuric acid below 70 ppm, and calcium hardness within the 200–400 ppm range specified for pebble-finish and plaster pool surfaces in Santee's mineral-heavy municipal water supply.