A drinking water system is a RO unit with an in-line carbon filter as the post filter to remove any abnormal tastes or odors. It normally comes with a pressurized storage tank and a RO faucet. They reduce the TDS down low enough for safe drinking water levels, but are not completely free of TDS.

Reefkeepers (discussed in the next FAQ) are RODI systems and provide -0- TDS water. Reefkeeping units do not come with any tank or faucet.

Pressure tanks are usually either a metal or plastic tank with a food-safe (plastic*) bladder. An air pocket that surrounds the bladder is what pressurizes the tank. This pressure gives you the amount you need to get water out of the faucet and/or the refrigerator.

Without the pressure tank, you can still get water out of the system, but not in good quantities. You can use a delivery pump to boost the pressure coming out of it to maintain good flow, but it's more costly.

Pressure tanks do have an adverse effect on the DI. This will be discussed more in the reefkeeping section related to the Dual Home Reef systems.

• The bladder will not leak anything back into the water. This is why it is "food-safe".

No, not really. It's helpful in keeping any strange tastes and odors from coming out of the unit, but isn't essential.

Why pre-install it if it isn't needed?

Everyone's water is different. We cannot determine what it will smell or taste like after the RO membrane. It's better to be safe than to be sorry.

Does adding a carbon filter after the membrane impact TDS?

It may or may not. Sometimes it inserts small amount of TDS back into the water. It doesn't hurt you so you don't have to worry about it. Most of the time, it doesn't do anything other than what it's supposed to.

You will need a permeate pump if you want to use your RO water for both drinking water from the RO faucet and get water from an icemaker/fridge. The permeate pump increases the pressure in the tank by filling it up more than what a RO membrane can on it's own. This causes higher outgoing pressure which many need in order to hook up their RO system to the fridge.

So, what if I already have really good pressure? Can I go with a basic system?

You can try to hook basic system if this is the case. We normally recommend trying hook-ups without pumps first to see if you actually need one or not. Though these are nice to have because of the extra benefits, they may not be needed.

For more information about this pump, please view our FAQ page on the different kinds of pumps.

Yes, no problem. This is a simple task. All you need is a couple of "T" or "Y" fittings and maybe a check valve.

Just keep in mind that each individual tank will fill up and release water as needed based upon location of the tank. One can fill up faster than another. This is normal.