How to Build a Reverse Osmosis System for Maple Sap

For many people, the time of year where sap begins to flow is a time for celebration. It is also an opportunity to start thinking about making syrup or sugar from the sap. However, that can be quite a difficult task to accomplish on your own since the process requires you to boil away all the water in order to concentrate the syrup. A reverse osmosis system (RO) is a great way to turn this process into a simple matter of filling up buckets with maple sap and waiting for it to seep through the RO membrane and be filtered into pure sap. Here are some helpful tips that will help you build your own RO system with minimal effort.

The Benefits of Reverse Osmosis

Reverse osmosis, or RO, is a method of purifying water by using a semipermeable membrane that only allows molecules to pass from the higher pressure side to the lower pressure side. This process has been used in industry for decades and is now being widely adopted in residential applications.

RO systems are especially great for filtering maple sap because they use two filters: a coarse filter and a fine filter. The coarse filter removes larger particles from the liquid while the finer filter blocks smaller particles. This process leaves you with pure maple syrup or sugar water which can be stored in buckets for later use.

RO systems also have a few other benefits that you might not be aware of:

1) Easy Maintenance – RO systems require very little maintenance since they don’t contain any moving parts.

2) Greater Capacity – RO systems are able to produce more water than other filtration methods like carbon filters which makes them ideal for large families or people living in areas with naturally occurring high levels of minerals like arsenic or lead which can be filtered out by an RO system.

3) Less Wastewater – With an RO system, wastewater is reduced significantly since only pure liquid passes through to your storage containers instead of contaminants.

Can You Build Your Own Reverse Osmosis System?

In order to do this, you will need a few pieces of equipment and a couple of parts. These include a pump, a membrane, tubing and a storage tank. Fortunately, these items are widely available for purchase or can be found at your local hardware store.

For example, you will want a membrane that is made from acrylic or polyamide fabric and has an active surface area of at least 1 square meter per cubic foot of water. You will also need to find tubing that can handle the pressure output from the pump without breaking and should be able to withstand chemical attacks such as acid and chlorine.

Next, you will want to choose a location for your RO system which should be near your maple tree because otherwise it would just be too labor intensive for you to collect sap each day then transport it back home. Afterward, the installation process is relatively easy: just connect the pump with your RO system and place it in proximity to your maple tree so that all of the sap can easily flow into it without getting blocked by anything else nearby. Then all you need to do is to place a container beneath the tubing so that the sap can collect in it.

Finally, you will need to make sure that your system is working properly by testing it with known pure water and then comparing the results of your test with what you got from your maple tree. If everything is satisfactory, then congratulations! You now have a way of producing pure water for free and harvesting some delicious maple syrup in the process!

How to Plan Your System

Once you’ve decided on the right size RO system for your needs, you’ll need to construct it.

The membrane is what separates the water from the sugar (or syrup). It can be made out of anything that will allow water to pass through but not sugar. You also need a filtration system with at least two filters that can remove any impurities in the sap. Just like when you’re building a table, you want to make sure everything lines up correctly so it’s easy to clean and maintain.

It’s important to keep in mind that if your RO system isn’t built correctly or if you don’t have enough filtering systems in place, then your system will clog up and become ineffective. This will cause problems with your flow rate and could even ruin your membrane.

Once you’ve constructed the physical part of the RO system, there are some last steps to take before actually using it. The final step is adding acid which is nontoxic and helps remove any bacteria that might be lurking in the sap before it goes through the membrane. You want this for an added level of safety while boiling off all of the water from your sap to produce syrup or sugar.

Once the RO system has been connected with power, the water is pumped through the system, through the filters and then into a storage tank. The storage tank is where you’ll store your finished product before it’s ready to be used or bottled.

The RO system will produce an extremely pure product that’s crystal clear. This is important because if you don’t filter out all of the impurities, it might affect the color of your finished product.

This method of filtering sap isn’t for everyone and some people may prefer to use a more traditional method of evaporating the water from their sap using a pan or trough instead. This is fine as well and both methods work well, but in my opinion, this RO system takes less time and produces a higher quality product.

Build Your Own Maple Syrup Reverse Osmosis Rig

Choose Your Equipment for Your System

There are a few different items you need in order to make a reverse osmosis water filter system.

The first thing you will need is a fitted plastic bucket. Next, you will need a rigid plastic tube, preferably one that is around four inches wide and about 50 feet long. You will also need a 3-inch diameter hole saw and an electric drill.

Lastly, you will need the RO membrane and some tubing to go with it: two inches for the input and output on your system.

Materials for Building Your System

  1. A large tank. The tank should be at least 7′ long and 4′ in diameter with a minimum of a 12 gallon capacity. It is also a good idea to have a spigot that will allow you to drain the sap every day without having to remove the system from the tree it is tapped from.
  2. PVC pipes. The pipes should be sized so that they match the size of your tank, typically 2″ or 3″.
  3. PVC fittings for your pipes, including unions, elbows, and T fittings for both 1/2″ and 3/4″ pipe diameters.
  4. For the filter:
    • 3″x6′ RO membrane
    • 2″x5′ RO membrane
    • 9″x9″ bag of activated charcoal (or other filtration material)

Choosing the Right Components for Your System

First, you need to determine the right size for your RO system. This will depend on how much sap you want to filter at a time. If you have a small goal of just filtering 10 gallons, then a 5 gallon system will do the trick for you. However, if you want to filter 20 gallons at a time and your pump is capable of handling it, then go with a 10 gallon system.

Additionally, make sure you choose the right material for your container. You can find plastic containers or buckets that work well for this purpose. Choose whatever will suit your needs best!

How Much Water Does Reverse Osmosis Take Out of Maple Sap?

The amount of water a RO system can take out of sap depends on a few factors. The size of the membrane is a key factor in determining how much water is removed from the sap. For example, a small 1 micron filtration membrane will filter out up to 90 percent of the water from sap, while a larger 25 micron filtration membrane will remove as little as 10 percent.

In addition, the pressure applied to the sap during filtration will affect how much water is removed from it. The more pressure applied, the more water that will be filtered out of your sap. A medium-sized maple tree should yield about 33 gallons of sap per day, which means that a small 1 micron membrane can process about 3 gallons per day and a 25 micron membrane can process up to 10 gallons per day.

How Does Reverse Osmosis Work With Maple Syrup?

Reverse osmosis, or RO, is a process that removes many of the impurities from water. In the case of maple sap, this process will remove much of the water content, which can take up to six hours in a traditional system.

RO works by forcing water through a membrane under pressure and collecting pure water on one side and dirty water on the other. The membrane used for RO is made up of tiny pores that allow water molecules to pass through it but not larger particles like solids and minerals.

The process starts with connecting your RO system to your storage tank with tubing and filling up your storage tank with sap. Next, you’ll want to add an RO filter cart to the top of your storage tank so that when you pump sap into it, it will filter though the cart before going into the tank.

One thing you’ll need to consider before building your RO system is how much sap you’ll need to produce each day in order for it to be worth having an RO system and how much time you’re willing to spend boiling down sap every day. If you only need a small amount or if you’re not interested in spending time boiling down sap every day, then an RO system might not be for you.

If you have a lot of sap to produce and you’re willing to spend time boiling it down every day, then an RO system is a good option. If you don’t have a lot of sap or aren’t interested in boiling down large amounts every day, then an RO system might not be for you.

Save time & money making syrup with a DIY Reverse Osmosis filter ( RO filter ) w building directions

Does Reverse Osmosis Change the Flavor of Maple Syrup?

Some people have been worried that the flavor of maple syrup will be changed by the RO process. In fact, the opposite is true. Reverse osmosis does not change the flavor at all.

The only time you would notice a difference in taste is when your RO membranes are dirty or aren’t able to remove all minerals from the water. If this is a concern, then it’s important to clean out your RO system regularly and replace your membranes with a new set occasionally.

What you should worry more about is making sure that your sap flows through enough to make it worth it for you to invest in an RO system. The most effective way for sap to flow through is if you collect sap in buckets and wait for it run through on its own without doing anything else (it could take up to 24 hours).

However, if you need faster results, then there are many helpful tips that can provide assistance: heat up your sap before running it through the RO membrane; use a pump to force sap through quickly; and buy a large RO membrane so that more sap can be processed with less effort (just make sure the membrane isn’t too stiff and fragile).


You can enjoy all the benefits of reverse osmosis with your maple sap. With a little planning and a little know-how, you can have fresh, delicious maple syrup year-round.

Meet the author: Jessica Chen

Jessica is a fishing enthusiast and yoga fanatic who enjoys traveling the world and reading books about Buddhism. She has a passion for writing, food, and wine. “Winter is my favorite season. I love sitting by the fire with a good book and a warm cup of hot chocolate.” Learn more about Jessica and the rest of the team.