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  • FREE Shipping On $175+
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RO/DI Systems
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Here's the deal
When you buy a reverse osmosis (RO) or reverse osmosis deionization (RO/DI) system from, you’ll receive 15% off all your replacement sediment filters, carbon filters, DI cartridges and membranes FOR LIFE.

So how does it work? Simple!

Just purchase any RO or RO/DI unit you desire from our online store. Any order you place thereafter that includes a replacement sediment filter, carbon filter, DI cartridge or membrane will automatically have your 15% discount applied when we process your order. You don’t have to do a thing!

Shop RO/DI Systems & Accessories

Aquarium reverse osmosis systems remove impurities from tap water to ensure your aquarium is free from heavy metals, pesticides, phosphates, chlorine and chloramines. Aquarium reverse osmosis systems are commonly abbreviated as RO systems; reverse osmosis/deionization units are generally referred to as RO/DI units. Aquarium reverse osmosis filters are available in economy 2-stage units and top-of-the-line 4-stage units. While an aquarium reverse osmosis unit is useful for all saltwater aquariums, RO/DI units are recommended for saltwater reef aquariums. By utilizing’s “15% off for Life” promotion, you’ll receive 15% off all your aquarium reverse osmosis water sediment filters, carbon filters, DI cartridges and reverse osmosis filtration membranes when you purchase an RO or RO/DI unit from our store.

This item is temporarily unavailable but will be back in stock soon.

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Click the Add To Cart button below if you'd like to reserve this item today. Any other items included in your order will be immediately processed and shipped. We will ship this item separately as soon as it arrives. We will not charge you for this item until it ships and you will incur no additional shipping charges.

Enter your email address in the field below and click the Notify Me button if you'd like us to send you an email when this item becomes available. Although you will be immediately notified when we have stock on hand, we will not reserve any units for you; you must return to our website and place an order.

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