RO/DI Reef Tank Systems Are More Important Than You Think – Here’s Why

While you can spend thousands of dollars and countless hours tending to the myriad of components needed to support a healthy reef environment, but without pure water, these efforts are in vain. For many reefers, it’s far too easy to become caught up in the finer details of this hobby.

Even though each tank element impacts the vitality of this contained ecosystem, failure to understand the influence of water quality is essentially consenting to the demise of your self-created underwater universe.

Just as air quality and purity impacts human health, water quality directly influences the growth, coloration and continued development of all tank inhabitants. Establishing a harmonious microcosm may require a multitude of chemical and biological adjustments, but in this article, we’re focusing on the most important out of all these: choosing a water source.

Reef Keeper? More Like Water Keeper.

Recently, I heard a small statement that perfectly describes the baseline of what it means to be a successful reef keeper. Although the ultimately goal of this hobby is to create a healthy environment to enjoy the visual brilliance of corals, fish and other saltwater tank inhabitants, if you look at the fundamental pillars of this hobby, we’re more like water keepers than reef keepers.

At first, I shrugged this statement off as a way to simply distill the importance of high quality water. It wasn’t until I had a little time to marinate on this concept that it truly hit home.

We are, in fact, primarily water keepers. Think about it. In the wild, what destroys marine life the fastest? Water contamination and pollution. Moreover, without a perfectly balanced water composition, life itself wouldn’t be possible within these environments.

For many reefers, the convenience of sourcing water from their household tap is just too great to ignore. After speaking with many hobbyists, those who primarily use tap water have strikingly similar reasonings.

Easy and Dangerous - Tap Water for Reef Aquariums.

Before diving into the benefits and impact of RODI water systems, you simply won’t grasp its true value if you don’t understand the implications of using tap water.

This shouldn’t come as a surprise, but I adore shortcuts. Life’s too complicated as it is, so I’m always on the hunt for daily living and reefing hacks. I guess you already knew this, considering the name of this website. However, even I understand that not all hacks are good, no matter how much time or money they may initially save.

When it comes to reef tank water, the biggest threat is also the easiest to use.

In the minds of many aquarists, there are few words that send them into a state of frustration as quickly as “tap water.” Throughout my experience, I can’t begin to explain how many times a novice reefer has asked for help with an underperforming tank that sourced water straight from the tap.

Confused and desperate for answers, these reefers looked at me with wide eyes as I said, “Let me guess, you’re using tap water?” I can see their thoughts search for a response beyond a simple acknowledgment.

More times than not, their answers begin to explain that even thought they do use tap water, they treat it with some type of conditioner. Or, better yet, they quickly say yes and then go into a detailed explanation of how they implement a laundry list of nutrient export and nutritive supplement methods.

Here’s a hard truth that many have a difficult time accepting:

Just because tap water is relatively harmless for humans doesn’t mean the same for sensitive invertebrates, like coral. In fact, the chemical composition of tap water can be deadly.

You see, tap water has so much more than trace amounts of chemical cleaning agents. The average city in the United States doses all those who drink from its tap water with inorganic and organic compounds, metals, phosphates, nitrates and even antibiotics. While a water conditioner can remove the most of the more prominent chemicals, it’s not even close to the purity standards your aquarium requires.

This is where RODI systems come into play. Few water purification systems deliver results to the degree as this advanced filtration method. Not convinced? Let’s dive a little deeper into why RODI water systems may hold the key to unlocking your tank’s true potential.

RO/DI Water Systems - What’s the Deal?

In an ideal world, we’d all have access to fresh and natural seawater. While a select number of reefers can leverage the bioactive realm of seawater, the other 99% of us must turn to more creative, and sometimes cumbersome, sources.

When compared to only a few years ago, reefing science and technologies is almost unrecognizable. As researchers unearthed hidden secrets of not only seawater composition, but how common foods and additives impact the molecular realm of tank water, the era of refined reef keeping began.

Perhaps the greatest evolution to come out of this reefing renaissance period is the influence of tap water on marine life. While it’s been generally accepted for many years that untreated tap water is harmful, there was an audible gasp among the reefing community as news spread about the negative influence of treated tap water.

This revelation has changed the way many of the world’s top reef aquarists view water sources. So, what’s this mean for you? In essence, it means the access to previously expensive and under recognized water purification RODI systems is now easier (and more affordable) than ever before.

Proudly resting at the top of this list is RODI water systems. Capable of extracting nearly 100% of common tap water contaminants, these innovative water filtering devices are literally changing how reefers view water.

RO/DI Filtration Systems - An Investigation Into Purity.

If you’ve never heard of reverse osmosis, then you must not own a television or computer. This incredibly effective purification process has long been used by aquarists, not to mention consumers searching for cleaner water, for many years.

R/O Meaning.

Essentially, reverse osmosis is a potent purification method thanks to its multistage filtration process. Without diving into too much detail, here’s a brief explanation of reverse osmosis:

• As an important natural phenomenon, osmosis occurs when water with a lower saline concentration migrates to water with higher saline concentrations.

• Reverse osmosis, as you’ve probably guessed, is the reversal of this phenomenon. Instead of low migrating to high, the higher saline water is forced through a semipermeable membrane, such as a filter. While water passes through the filter, the majority of other compounds (organics, bacteria, salts, etc) doesn’t, which results in purified water.

• The first stage of R/O filtration is when pressurized water moves through a pre-filter, which removes micron sediment (sand, silt, clay sediment, etc) that would otherwise inhibit R/O membrane functionality.

• The second stage involves the now semi-filtered water passing through an activated carbon filter, which absorbs a variety of contaminants and minerals, such as chlorine, chromium, pesticides, etc.

It’s important to note that there are many different types of specialized filters capable of extracting unique compounds, such as chloramines (Example: Pentek ChlorPlus 10). To maximize filtration benefits, consult your local water municipality to determine what disinfectants and other chemicals they employ.

Now that water has passed through the R/O filtration system, it moves into the next stage: deionization.

DI definition - What does DI mean.

As water passes through the deionization (DI) cartridge, synthetic resins remove both positively (cations) and negatively (anions) charged ions and replace them with hydrogen (H+ and H-) ions. I know, this sounds extremely complicated, but the only thing you need to understand is this purification process doesn’t simply filter harmful compounds and chemicals. It literally alters the molecular structure of water.

It’s important to note that this explanation is extremely simplified. While these are the baseline stages, the majority of recommended RODI systems offer anywhere from 4 to 5 stages of filtration.

No wonder RO/DI systems are the most commonly used water purifiers among professional aquarists and RODI water is a popular item at fish stores. So, now that we’ve covered the basics, let’s get into how you can implement this powerful system in your tank.

Quality Water Without the Wait - RO/DI Systems At Home.

When it comes to RODI filtration systems, one of the most common questions I’m asked is what system is best? Well, my dear reefer, the answer isn’t as simple as you may want.

As with almost every high-quality system in our hobby, it’s difficult to ascend one brand as the 100% best option. Because your reef tank setup and needs are wholly unique, the only way to determine the best for you is to know what features and capabilities are most impactful. From here, it’s possible to narrow down your choice to a system that’s perfect for you.

With this in mind, here’s a brief overview of three systems I personally recommend. Use this info to help guide your understanding and expectations of current system options. Keep in mind, that SpectraPure and AQUAFx offer a wide range of units that will fit any needs and budgets.

SpectraPure MaxCap Performance Plus.

This is the RO/DI unit that I’m using for my RODI systems. Delivering 5 stages of filtration, the SpectraPure MaxCap Performance Plus is considered an ultra high efficiency RO/DI system. Essentially, this robust system is designed to optimize purification without demanding a significant amount of power. While there’s a lot to say about the SpectraPure MaxCap Performance Plus RO/DI water filtration system and you can read about it in this article in details, let’s just stick to the most essential information:

• Capable of producing 100+ gallons of purified water in a 24-hour period (way more than enough for even the most demanding of reefer).

• Enhanced membrane life and DI cartridge operational life. One of my favorite features is the automatic membrane flush, which actively safeguards the functionality of the membrane for not only extended use, but also higher quality water output from beginning to end.

• Optimized pumping system, which is perfect if you have a low-pressure watering system (this SpectraPure RODI system operates with a pressure as low as 20 psi).

• Incredibly easy setup and maintenance, in fact, the unique filter wrench design makes removing the pre-filter and DI cartridges a breeze (something you’ll enjoy if you’re not the “handy” type). 

• Water level monitoring via two digital floating sensors, which helps safeguard water levels to ensure optimized functionality and safety. 

• Throughout the filtering process, two double double sensors monitor TDS readings at each of the four filtering stages. This offers invaluable insights into real-time TDS removal, which is important to ensure the system is doing its job.  

Please read our full review of the SpectraPure MaxCap Performance Plus for more details, click here.

Obviously, this is only of a sampling of the features offered by this robust 5 stage RO/DI system. As you begin investigating RO/DI filtration systems, you’ll notice a specific trend of product-to-wastewater ratios. The goal is a 1:1 ratio, which is an impressive feat. Unlike many of its competitors, the SpectraPure MaxCap Performance Plus adheres to this promised ratio, which is something all reefers will enjoy.

AquaFx - The Barracuda 100 GPD Glacial.

While the aforementioned RO/DI products come highly recommended by reefers at all experience levels, The Barracuda 100 GPD Glacial is by-far the most celebrated.

Here’s a few highlights as to why it’s considered a top choice among serious reefers:

• Capable of being upgraded to produce up to 300 gallons of purified water per day (optional).

• Safety features as adjustable float valve for automatic shutoff and an easy-to-read pressure gauge.

• Single inline TDS meter, which simplifies understanding the rate of TDS removal.

• 4 stage design, which includes: Sediment Filter, Carbon Block (GAC or Chloramine Blaster), Reverse Osmosis Membrane and Deionization Filter.

• Significant improvement in both operation quality and durability when compared to the original Barracuda RODI water system.

If you’ll decide to get this RO/DI unit I’d recommend you to add one more stage of filtration and get the additional option called Chloramines Blaster.

Please read our full review of the AquaFx - The Barracuda 100 GPD Glacial for more details, click here.

I highly recommend checking out this RO/DI purification system, especially if you’ve never used one before. Not only does this device deliver high quality water, but its installation and maintenance is surprisingly straightforward. But the product-to-waste is around 1:4.

VerTex Puratek Deluxe 200 RO/DI.

The VerTex Puratek Deluxe 200 is regarded by many professional reefers as a solid option for both new and established tanks. Of course, this is easy to say, so what is it about this machine that truly sets it apart? Here’s a brief rundown:

• The entire RODI system is operated and monitored by a robust microprocessor, which basically means this is a “smart RO/DI system.” By leveraging the efficiency of a digital microprocessor, its operation is more refined than many of its competitors.
  
  
• Features are quite impressive. These include automated back flushing, TDS detection and electronic display and safety reservoir shutdown.

• Operates in a low-pressure environment, down to 20 PSI. It achieves a 1:1 product-to-waste ratio, which is powered by an impressive oil-filled pressure gauge. I find that the readouts are accurate and easy to interpret.

• Can produce up to 200 gallons of purified water per 24-hours, which is an awesome stat considering its robust dual RO membrane capable of extracting both organic and inorganic compounds.

• Leaks are virtually non-existent within this system thanks to its push-to-connect fitting design.

This is only a small portion of the features and capabilities. If you’re interested in a high-tech system, then you should definitely check it out.

While the aforementioned devices are considered the top, they’re not the only RODI water systems on the market worth your time and money. Check out these other recommended systems:

• SpectraPure® Maxpure 90 GPD RO/DI System.
• AquaFX Barracuda RO/DI Aquarium Filter.
• Aquatic Life Twist-In 100 Gpd 3-Stage Ro Unit.
• Marine Depot KleanWater 4-Stage Advanced RO/DI System - 100 GPD.

Cleaner Water Without the Hassle - Final Thoughts.

Sure, it’s possible to purchase RO/DI water from your local reefing store or the "purple cap" distilled water from Walmart, but honestly, it’s a pain. Installing a personal RO/DI system is, without a doubt, one of the best decisions you can make as a reefer. While these systems aren’t the cheapest devices, they pay for themselves when you witness their impact on your underwater universe and you can always find a unit that will fit  your budget and needs.

Before signing off, here’s one last hack:

When installing an RO/DI system, I recommend doing so on your ground-floor level. Even though these systems come with emergency shutoff systems, overflows and leaks are a possibility in even the most well-designed systems. By installing it on the first floor of your home, you’ll eliminate the risk of serious water damage should a leak occur.

There you have it! Be sure to head over to our Facebook Page and send us a message if you have any questions about RODI water systems. And, as always,

Happy Reefing!

by Yuliya Ivanova for ReefHacks.