WISRD Research & Engineering Journal

Figure 13. Left: Sponge in bottom tray. Right: Long sponges are positioned next to the stack of trays.

Figure 14. Sample polishing pads. 2.5 System for Making Seawater

2.5.1 Reverse Osmosis Deionized Water Filtration System We installed a 5 stage Premium 75 GPD reverse osmosis deionized (RO/DI) water system from Bulk Reef Supply (Fig. 15). Stage 1 contains a 1-micron sediment filter. Stages 2 and 3 are 1- micron carbon blocks. Stage 4 is a 75 GPD Dow Filmtec Membrane, which has a 3:1 waste to product water ratio. Stage 5 is a color changing deionization resin. The system was installed after an initial Aqua-Pure AP110 5-micron sediment filter. RO/DI water is stored in a 36” L x 20” H x 18” W acrylic holding tank (see Figure 16). This tank holds approximately 50 gallons, and we typically keep it half full to ensure at least 25 gallons of RO/DI water was available at all times.

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