RO system to control water parameters worth it?

[Aquajack]

Hi all,

First of all thanks so much for the amazing threads and input from all the super knowledgeable and experienced scapers on here.

My question and apologies if this has been specifically discussed previously, but I'm wondering if an RO system would be a worthwhile investment for a high tech planted tank.

My town water which I currently use is not on the grid with the main city water supply that I used to access. Our town water is sourced from a creek, not a huge reservoir, and can vary from time to time, more than I would like. For example, the PH can be anywhere from 7-8, KH when measured some months ago was 4dKH, is now 6. GH 7dGH.
I know they are still within reasonable bounds though.

I could look at ways to just lower KH using HCL for an example but that doesn't fix the stability of the water supply for the other elements.

I'm also not able to obtain a water report.

I've just put in a plant order for my new scape (which I think I'll start a journal on soon) that includes plants like Syngonanthus macrocaulon which prefers lower KH.

Ro a good investment or am I over thinking it?

 

[gnatster]

Ro a good investment

YES

 

[Naturescapes_Rocco]

After switching to RO water 6 years ago, I will NEVER go back to tap water. Every tank in my signature and journals is with RO water.

I've been using two of these systems for years now without issue.

For $160 upfront, and about $50 in filters per year, you can have pure water for your tank. You'll gain full control over all of your parameters, you'll never need to dechlorinate your water ever again, and you'll gain not only crystal clear water for your aquarium, but also pure water for drinking, cooking, DIY fertilizers and scientific uses, and for pure washing/rinsing (RO water makes for an amazing finishing cleaner on glass, mirrors, etc).

RO systems are plug and play, like lego bricks. You can add more, or less, or branch off to different storage methods.

If you have questions let me know, I'm a water nerd and love talking RO water!

 

[JacksonL]

With such a variable water supply, I think the answer is yes. Even if you’re fine with using KCl to lower kH, the added step of having to test tap water every time to check makes it even more of a bother than normal.

 

[Aquajack]

Thanks heaps Rocco as always.
Yes, the multiple use case is also compelling and an extra tick.

Is yours plumbed in under your sink?
For my situation, I'm more looking at setting it up connected to the laundry tap for example and having a reservoir sitting under that, so wont need a faucet, although if one could be setup for a portable system, then of course I'd look at it.

 

[Pepere]

My tap water is amazingly consistent. The source water is exceptionally soft.

The water district then raises Calcium to 5 ppm and Magnesium to q ppm and 2DKH.

I asked the director if the water district if there were seasonal variations…. His response is that the source water fluctuates some, but they always raise Calcium to, Mg and Carbonate hardness to stated numbers, they just vary how much they add…

For myself, with my tap water, I cant see any reason to take on the cost and effort of ro water. I simply supplement with calcium sulfate and epsom salts to raise to 36 ppm Ca and 6 ppm Mg.

I have reacted KH with Seachem acid Buffer to reduce KH to close to 0 but never noticed any benefit from it and when the bottle ran out I didnt replace it.

I am very thankful for our local tap water.

 

[JayP]

Another yes from me. I really like the control of using RO and knowing if I have an issue with something, it's not likely the water. Also, once my reservoir system was set up, water changes are actually easier than using tap water. I have hoses in the basement and main level and just run them to whichever tank I'm working on. The pump is on a smart plug, so I just ask Alexa to turn on the water pump when I'm ready to re-fill. I also have inline flow meters on each hose to keep track of water totals, although, all my tanks are marked for 50% water change so I already know exactly how much to remove (tip from @Naturescapes_Rocco ).

 

[Aquajack]

Another yes from me. I really like the control of using RO and knowing if I have an issue with something, it's not likely the water. Also, once my reservoir system was set up, water changes are actually easier than using tap water. I have hoses in the basement and main level and just run them to whichever tank I'm working on. The pump is on a smart plug, so I just ask Alexa to turn on the water pump when I'm ready to re-fill. I also have inline flow meters on each hose to keep track of water totals, although, all my tanks are marked for 50% water change so I already know exactly how much to remove (tip from @Naturescapes_Rocco ).

Sounds like a great setup. Like the pump setup too. I'm firmly in the google ecosystem haha. Same diff. Inline flow meters. I'll have to look into that. Every little thing makes our jobs easier when we do it many many times.

For the RODI I was just thinking something like below.

AquaticLife RODi 4 stage

 

[hamfist]

After switching to RO water , I will NEVER go back to tap water.

This.

 

[ElleDee]

My tap water is very soft (1.5 dKH ) with low TDS , so I have not bothered with RO. Am I leaving something on the table by doing this? Maybe, but I imagine the difference must be quite small.

 

[CincyScaper]

Hi, I think the need for RO is user dependent. In my part of Ohio we have quite hard water with both KH and Gh > 10-12. I could grow many plants quite well in an inert substrate without much fertilizers and without co2 and using a cheap light. These were beginner friendly plants such as crypts, Anubias, amazon swords, h.tripartitia, Ludwig’s and some rotalas. Montecarlo and other more difficult category plants did not grow well.

I wanted to grow these difficult plants and hence switched to RO. For me the waterdrop system works well, and we use it primarily for drinking as well. The absence of a reservoir was what I liked about these system. More expensive for sure. Although my plant growth is much better , if I ever wanted to keep just low demanding plants I would go back to tap water.

I think there is a wide spectrum of how much control one wants on water parameters and ferts in this hobby. I don’t think there is one perfect answer, just lot of preferences depending on what you are going for.

 

[Koan]

For the RODI I was just thinking something like below

Bear in mind the GPH you actually produce is going to be dependent on your water pressure, so many users find they get a much better result with a booster pump

Post in thread 'RO Water Barrel Maintenance'

Dec 27, 2025

Also, check your home's water pressure. To get the best performance out of these high gph (and least waste water) units. You want at least 60psi going into the unit. I have a hair under 60 so I plan to add a booster pump soon. The Waterdrop already has a built-in booster pump.

• JayP

• 

 

[Aquajack]

Bear in mind the GPH you actually produce is going to be dependent on your water pressure, so many users find they get a much better result with a booster pump

Post in thread 'RO Water Barrel Maintenance'

Dec 27, 2025

Also, check your home's water pressure. To get the best performance out of these high gph (and least waste water) units. You want at least 60psi going into the unit. I have a hair under 60 so I plan to add a booster pump soon. The Waterdrop already has a built-in booster pump.

• JayP

• 

Thanks Koan, I did see a few models can incorporate a booster pump and apparently it also reduces the waste water ratio which is something else to think about

 

[Aquajack]

Hi, I think the need for RO is user dependent. In my part of Ohio we have quite hard water with both KH and Gh > 10-12. I could grow many plants quite well in an inert substrate without much fertilizers and without co2 and using a cheap light. These were beginner friendly plants such as crypts, Anubias, amazon swords, h.tripartitia, Ludwig’s and some rotalas. Montecarlo and other more difficult category plants did not grow well.

I wanted to grow these difficult plants and hence switched to RO. For me the waterdrop system works well, and we use it primarily for drinking as well. The absence of a reservoir was what I liked about these system. More expensive for sure. Although my plant growth is much better , if I ever wanted to keep just low demanding plants I would go back to tap water.

I think there is a wide spectrum of how much control one wants on water parameters and ferts in this hobby. I don’t think there is one perfect answer, just lot of preferences depending on what you are going for.

My numbers may not be exactly like yours but my idea/strategy is similar. I currently don't have any real high demanding plants but I would like to grow them and in fact have a few on order. To grow these types of plants and have full control over your parameters is what I'm after.

 

[JacksonL]

My tap water is very soft (1.5 dKH) with low TDS, so I have not bothered with RO. Am I leaving something on the table by doing this? Maybe, but I imagine the difference must be quite small.

I doubt you are missing out on much. I’m jealous of people with tap water like yours.

 

[hamfist]

......... a booster pump and apparently it also reduces the waste water ratio which is something else to think about

When I added a booster pump it doubled the efficiency of my system, and thus also halved waste water.

I also run a small fan to cool the booster pump. This way I can ignore the restrictions that they all seem to quote of only running the booster pump for 2 hours at a time. Without the fan, the pump heats up noticeably but with the fan blowing on it, it does not heat up at all. I can run it all day and all night, no heating up, no problem. I have been doing this once a week for around a year now, so I am convinced it is a reasonable strategy

 

[Minninips]

I've cobbled together a RO system using Rocco's recommended set from Amazon. What I could use some pointers for is the setup and transfer to the tanks. Since we're on the topic, I figured maybe this is a good place to ask.

Has anyone documented their setup? Like a guide or advice on connecting barrels, heating, plumbing, pros/cons of re-mineralizing in a barrel vs tank? @Noahspapa made a post that has some good info, but I'm hoping for a bit more clarity before I start ordering random parts and hoping for the best.

For anyone that wants to have a mental picture of me, I'm over here turning on the included faucet to fill a 55g trash can, eventually transferring to a 44g trash can, rolling the can out to my tank, filling the tank from there, rolling the can back to the laundry room with excess, and rinsing and repeating each week. Fish are coming this week, so I think it'll be important to start heating my water. It comes our pretty cold and drops my tank temp by over 10 degrees when I do the water change (and that's after sitting in the laundry room for over a day).

 

[Noahspapa]

Hi Minninips. I’ll provide some additional input on my setup later today as one data point for you to consider.

 

[Koan]

Has anyone documented their setup?

@Naturescapes_Rocco has..

Post in thread 'Home RO set up for aquarium and drinking'

Jul 29, 2025

Preparing to get parts to setup up my larger storage tank. What pump are you using?

See my post #37 here! I use a diaphragm pump. They are a pressure-focused pump that self-primes, so you don't have to prime them yourself. They can suck air dry completely and start sucking water like a vacuum when it's available. I use one of these, I believe. Been running 1-2 times a week for a year without issues, pumping from the basement upstairs!

The storage tanks I'm using are two Brute 55 Gal trash cans. I drilled each near the bottom and installed:

1. these 3/4"...

• Naturescapes_Rocco

• 
• 

Journal Post in thread 'Currently 75 gallon walstad-like tank, soon to be UNS 120 after moving'

Jul 1, 2025

Install the RO system post-softener, since RO's are much better at filtering sodium out of soft water than calcium out of hard water. Softened water will greatly increase the lifespan of the membrane.

I would create a two-part system, with one part dedicated solely to ATO and another part dedicated to full WC. That's how I did it, for full redundancy/flood prevention/safety.

On the WC side:
get a 55 gal plastic drum off of FB Marketplace for $5:


Rinse it with your hose for an hour, drill a hole in it, and install an adjustable float valve. Here's the one I've...

• Naturescapes_Rocco

• 
• 
• 

 

[Naturescapes_Rocco]

I've cobbled together a RO system using Rocco's recommended set from Amazon. What I could use some pointers for is the setup and transfer to the tanks. Since we're on the topic, I figured maybe this is a good place to ask.

Has anyone documented their setup? Like a guide or advice on connecting barrels, heating, plumbing, pros/cons of re-mineralizing in a barrel vs tank? @Noahspapa made a post that has some good info, but I'm hoping for a bit more clarity before I start ordering random parts and hoping for the best.

Here's how my big tank is setup:

Cool features:​

• Because I prefer large water changes, I needed a way to get the incoming water "lower" in the tank, because I was constantly digging up my substrate and uprooting plants (the tank is 60cm tall). Turns out, you can just rearrange the parts in an FZone Lily Pipe set to make the perfect low-disturbance water adding pipe!
• Because diaphragm pumps turn off when the desired pressure within the tubing is reached (a valve is closed) you can add a valve inline as an emergency stop which will turn the pump off.
• Diaphragm pumps are really high-pressure pumps. If you were pumping across a single floor, you could use a regular pump. But pumping up from a basement requires a decent power pump, and diaphragm pumps were literally designed with this in mind!
• By using a smart plug (and closing the inline valve when not in use), not only can your water system prevent random turn-ons, you also can't accidentally turn the pump on without your phone or smart speaker.
  • Even better, you can program the pump to "Turn off [x minutes] after you turn on", so you can have a semi-automated set-it-and-forget-it system that never overflows your tank. I've been doing this weekly for over 1.5 years now.

Parts I used:​

• Brute 55gal Cans (x2)
• Express Water RO system
• Aquatic Life Float Valve
• Enoch's Land PVC 3/4" Rain Barrel Spigot
• 3/4" PVC Piping to connect barrels and Tee off to pump together
• Various adapters to go from the 3/4" PVC to the 1/2" tubing needed for the diaphragm pump
• 3.5 Gallon per Minute Eco Worthy 55PSI Diaphragm Pump
• GHome Smart Plug and SmartLife app
• 1/2" PEX tubing, ran from basement up through floor to aquarium
• Fzone 16/22mm Lily Pipes for water adding pipe

I never add ferts/salts to the storage barrels, instead I dose the aquarium after I've added the water! I just find the pros to be better than the cons for me in this case.

Again I'm not saying this is the only way to do this, this is just how I do it!