My plan for an RO/DI filter

[Cjbear087]

So I have a water softener connected to my faucet, and I’ve heard it isn’t very good for fish and especially plants. I am going to buy a RODI machine to remove everything and make it safe again. So basically plan is to set up the ro machine, fill bucket up 2 days before wc (do wcs on Saturday so fill thursday) heat on Friday (keep heater in overnight) then sat morning clean tank remove water etc. remineralise the water and use water pump to refill tank. Am I missing anything? I think this is everything I need to do, and will this mean even though the water has been softened beforehand it will now be okay? Thanks

[AllFishNoBrakes]

Should be fine. RO/DI basically leaves you with just pure water, so remineralizing, bringing it up to temp, and then doing a water change is what I would do. 

[Lennie]

I have water softener in my home system and I have all my tanks planted, and I keep many different fish snails and shrimp. It gives me a tds around 370 tho, and I use gh+ to remineralize.

Im not sure if every system is the same, but it is very much doable in my experience. I also have RODI but I only use it in my reef tank ans top ups or specific breeding tank if I really wanna try anything

On 4/4/2024 at 2:22 AM, Lennie said:

I have water softener in my home system and I have all my tanks planted, and I keep many different fish snails and shrimp. It gives me a tds around 370 tho, and I use gh+ and mont. clay to remineralize.

Im not sure if every system is the same, but it is very much doable in my experience. I also have RODI but I only use it in my reef tank ans top ups or specific breeding tank if I really wanna try anything

 

[Cjbear087]

On 4/4/2024 at 12:22 AM, Lennie said:

I have water softener in my home system and I have all my tanks planted, and I keep many different fish snails and shrimp. It gives me a tds around 370 tho, and I use gh+ to remineralize.

Im not sure if every system is the same, but it is very much doable in my experience. I also have RODI but I only use it in my reef tank ans top ups or specific breeding tank if I really wanna try anything

 

So you don’t think I need an RO filter? And I can just use the softened water if it is remineralised?

[Lennie]

On 4/4/2024 at 2:24 AM, Cjbear087 said:

So you don’t think I need an RO filter? And I can just use the softened water if it is remineralised?

Thats what I do in majority of my tanks.

Idk how experienced you are in the hobby, but stability is important for long term fish/tank health, and it might be a struggle for a person to keep the tank stable with RODI. It is considerably easy with reef tanks, because reef salt more or less prepares the RODI water to an ideal reef tank water once you mix the salt.

However, thats not the case for the freshwater part and you basically need to do it manually. Like kh, ph, gh…

What fish do you wanna keep?

[Cjbear087]

On 4/4/2024 at 12:31 AM, Lennie said:

Thats what I do in majority of my tanks.

Idk how experienced you are in the hobby, but stability is important for long term fish/tank health, and it might be a struggle for a person to keep the tank stable with RODI. It is considerably easy with reef tanks, because reef salt more or less prepares the RODI water to an ideal reef tank water once you mix the salt.

However, thats not the case for the freshwater part and you basically need to do it manually. Like kh, ph, gh…

What fish do you wanna keep?

I think I’m going to get some discus and a few other fish just not sure yet

[Lennie]

On 4/4/2024 at 2:35 AM, Cjbear087 said:

I think I’m going to get some discus and a few other fish just not sure yet

For the discus part, you better ask about it in simplydiscus forum. They are whole another world and discus only forum would help you better.
 

But, you will be expected to know about your parameters in order to receive better help regarding your questions on RODI and water softener ( which directly affects your tap I assume)

[Tony s]

I do the ro part. For fresh, you really don’t need the di part. But, you might just try the softened water. It’s really not that much salt. We hooked up a hydrogen peroxide injector to clear iron bacteria. It also clears beneficial bacteria. Hence the Ro. I don’t think I would use it otherwise. It’s kind of a pain to keep consistent. But I also use a 30g plastic trash can to mineralize in. Not remineralizing in the tank. Not everything dissolves either. Not even using a slurry 
 

 

@Cjbear087ask @jwcarlson about his discus. He keeps them in hard water. Very clean water. Healthy fish but no breeding. 

Edited April 3 by Tony s

[jwcarlson]

I'd put a bypass around your water softener and just use tap water for your fish, unless you're breeding something that needs very soft water.  I'm not convinced that hard water cannot work for most fish.  I've kept a bunch of different "soft water" fish over my years in the hobby including discus, apistos, and rams (rams are fairly recent addition) and I don't think it causes any issues as long as you maintain your tank.

[Cjbear087]

On 4/4/2024 at 3:05 AM, jwcarlson said:

I'd put a bypass around your water softener and just use tap water for your fish, unless you're breeding something that needs very soft water.  I'm not convinced that hard water cannot work for most fish.  I've kept a bunch of different "soft water" fish over my years in the hobby including discus, apistos, and rams (rams are fairly recent addition) and I don't think it causes any issues as long as you maintain your tank.

Are they cheap and easy to install?

[madmark285]

On 4/4/2024 at 3:57 AM, Cjbear087 said:

Are they cheap and easy to install?

A bypass would just be a value connected on the main water line before the water softener, most likely you already have one. It is difficult to give advice as this is a home plumbing issue, I don't understand "water softener connected to my faucet"? Is this a small device connected to one faucet? Or do you have a large softener on the main water line?

Another option, instead of Discus, go with African cichlids from  the rift lakes (Mbuna, haps or peacocks). They love hard water. 

Wise advice I use for aquariums, the more difficult it is to maintain your tanks, the higher probability you will not maintain them properly. Adding a RODI just makes it more complicated. 

[Cjbear087]

On 4/4/2024 at 9:41 AM, madmark285 said:

A bypass would just be a value connected on the main water line before the water softener, most likely you already have one. It is difficult to give advice as this is a home plumbing issue, I don't understand "water softener connected to my faucet"? Is this a small device connected to one faucet? Or do you have a large softener on the main water line?

Another option, instead of Discus, go with African cichlids from  the rift lakes (Mbuna, haps or peacocks). They love hard water. 

Wise advice I use for aquariums, the more difficult it is to maintain your tanks, the higher probability you will not maintain them properly. Adding a RODI just makes it more complicated. 

Yeah it is on the main water line

[jwcarlson]

On 4/4/2024 at 2:57 AM, Cjbear087 said:

Are they cheap and easy to install?

Yep, and like noted many people already have one.  We have one for our kitchen cold water.

I cut into that line and supply the cold for my utility sink in the basement where all my fish water comes from.

If you do go with RO, you will want to use the softened water for that as the membrane will last longer.

I age and preheat all of my water as I have a very big pH shift when my water is aerated for 24 hours.  That's another important thing to check as well.

Edited April 4 by jwcarlson

[madmark285]

On 4/4/2024 at 4:45 AM, Cjbear087 said:

Yeah it is on the main water line

So look for a value. If you have outdoor faucets, most likely they are connected before the water softener. Of course the next question is, can you get the water to a convenient location? I am an old guy, the days are carrying 5 gallon buckets of water are long gone. I ran a hose to a 32 gallon trash can, use a pump to fill the tanks. How big is your aquarium(s)? 

 

 

Edited April 4 by madmark285

[Cjbear087]

On 4/4/2024 at 10:33 AM, madmark285 said:

So look for a value. If you have outdoor faucets, most likely they are connected before the water softener. Of course the next question is, can you get the water to a convenient location? I am an old guy, the days are carrying 5 gallon buckets of water are long gone. I ran a hose to a 32 gallon trash can, use a pump to fill the tanks. How big is your aquarium(s)? 

 

 

I havent got it yet but it will be 90gallons. So I think if I use the bypass valve I will be able to use the water in my bathrooms after letting it run for a few minutes. Is there a way to test if the water is still being softened or if it’s normal once I’ve shut off the valve?

[Tony s]

Depending on the age of the system. It might already be built in. There’s usually a valve at the softener. 3 positions. Softener on, softener off, and softener bypass. Even the one we had in the old house had that. And that was 30 years ago. If it has that. Turn it to bypass and use your regular water lines

[Cjbear087]

On 4/4/2024 at 10:58 AM, Tony s said:

Depending on the age of the system. It might already be built in. There’s usually a valve at the softener. 3 positions. Softener on, softener off, and softener bypass. Even the one we had in the old house had that. And that was 30 years ago. If it has that. Turn it to bypass and use your regular water lines

What is the difference between softener off and bypass?

[TOtrees]

lots of useful info in this thread. i've never thought of softened water as "stripped but with salt", but that seems to be one way to view it, based on one user's suggestion above to remineralize it. so basically it isn't just that the salt might be an issue, but rather softened water has low/insufficient levels of what fish/plants need, and lots of what they don't. also the suggestion to supply the RO membrane with softener output water is a new one for me, makes sense. 

And no i'm not trying to make always-true blanket statements here, just noting likelihoods or often-true conditions. 

[Tony s]

On 4/4/2024 at 6:28 AM, Cjbear087 said:

What is the difference between softener off and bypass?

Softener off means no water at all. In case you have a sediment filter to change. Softener bypass lets the water flow but without going through the softener. So straight well water. 

 

On 4/4/2024 at 8:02 AM, TOtrees said:

i've never thought of softened water as "stripped but with salt

That’s the easiest way to think about it. In reality, the membrane is used to remove remove the calcium. I say membrane, but the membrane is usually a 3 to 4 foot tall tank. Kind of looks like an oxygen tank used in welding. The salt is used to reset the membrane 

[madmark285]

On 4/4/2024 at 5:50 AM, Cjbear087 said:

So I think if I use the bypass valve I will be able to use the water in my bathrooms

Yes, that would be correct. And my apologies, I may be confusing the issue. My suggestion was, see if you already have a value before the water softener.  Below is a picture on how a plumbing may build a bypass system using individual values. 

So with a 90 gallon tank, a 20% water change would be 18 gallons. What many do here including myself, find a place in your house for a 32 gallon garbage can. I use a Brute brand from Home depot. This would require a cheap water pump to refill the tanks. 

Second question, how are you going to drain the water out of the tank? Many here use the python system which could also be used to fill the garbage can/buckets. 

[Tony s]

On 4/4/2024 at 8:02 AM, TOtrees said:

And no i'm not trying to make always-true blanket statements here

Nothing wrong with blanket statements. Sometimes it’s the easiest way to move information along. With the caveat that nothing works in every situation. This is biology we’re talking about. Sometimes just the littlest thing changes things an enormous amount 

[Tony s]

@madmark285  nice diagram. That’s one that can easily be done. The two systems I’ve had only had one three position valve though. Much more convenient, and the companies caught on. Because there should be a sediment filter before the softener. Otherwise you fill your softener with gunk. Or your pipes. Nobody said well water was clean🤣  but actually much tastier than bottled. Unless you have sulfur in it. 🤮  thank goodness. None of our houses have any of that. 

[Cjbear087]

On 4/4/2024 at 1:44 PM, madmark285 said:

Yes, that would be correct. And my apologies, I may be confusing the issue. My suggestion was, see if you already have a value before the water softener.  Below is a picture on how a plumbing may build a bypass system using individual values. 

So with a 90 gallon tank, a 20% water change would be 18 gallons. What many do here including myself, find a place in your house for a 32 gallon garbage can. I use a Brute brand from Home depot. This would require a cheap water pump to refill the tanks. 

Second question, how are you going to drain the water out of the tank? Many here use the python system which could also be used to fill the garbage can/buckets. 

This was exactly my plan, I was even thinking about getting a Brute. To drain I was just going to use a normal gravel vac and have the pipe go straight into my sink. Python seems unnecessary as I won’t be using it to fill the tank so a normal vac will suffice

[jwcarlson]

On 4/4/2024 at 7:02 AM, TOtrees said:

lots of useful info in this thread. i've never thought of softened water as "stripped but with salt", but that seems to be one way to view it, based on one user's suggestion above to remineralize it. so basically it isn't just that the salt might be an issue, but rather softened water has low/insufficient levels of what fish/plants need, and lots of what they don't. also the suggestion to supply the RO membrane with softener output water is a new one for me, makes sense. 

And no i'm not trying to make always-true blanket statements here, just noting likelihoods or often-true conditions. 

I do not know if this is a legitimate concern or not, but the standard ion exchange softeners strip out minerals and replace them with, on average, two sodium ions.  Some people claim that "TDS" makes a difference.  I don't know if that's true or not.  But my tap water is like 300 TDS and my softened water is 600+ TDS. 

 

@Tony s is correct.  There is often a bypass valve built into a softener.  The issue is if you're going to use straight tap water, you also have to factor in the time it's going to take to get that water into your water heater and up to temp.  And how much do you purge from your water heater before you have purged the softened stuff?  I would suggest putting in a full-time bypass if it's a hose bibb or a connection to one specific sink you use for your fish water.  But you're going to have to use straight cold tap water for that as the hot water supply will be softened water.  All of that monkeying around creates a good chance of providing inconsistent water to your fish, which if you take nothing else away from this thread... that's what you want to avoid.

I have a cold tap supply in my utility sink where I fill my 63 gallon aging/preheating barrels from.  I have a >1.0 pH shift (something like 1.2 or 1.3 shift up), so I age my water.  When I need straight RO water for my breeding setups, I have a long 1/4" line that I unwind and run over to one of the barrels and fill it up.  My RO Buddie unit takes quite awhile to fill the 63 gallon barrel about 14 hours or more.  Someday I'm going to get around to installing a float valve so that I can not have to worry so much about accidently leaving the RO on.  Each barrel has it's own heat controller and aeration setup so that I can do more than one water change at a time.  Though I basically either have 82 degree water or 76 degree water, so they're not terribly far off.  But I don't want to do a 90% water change with water that different in most cases.  So having some flexibility is nice.

On 4/4/2024 at 7:33 AM, Tony s said:

That’s the easiest way to think about it. In reality, the membrane is used to remove remove the calcium. I say membrane, but the membrane is usually a 3 to 4 foot tall tank. Kind of looks like an oxygen tank used in welding. The salt is used to reset the membrane 

It's an ion exchanging resin bed in the tank.

Edited April 4 by jwcarlson

[Cjbear087]

How easy / expensive is it to setup a bypass for one specific sink? I imagine ill need a plumber?