RODI system setup

Spartyon

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Hello out there, I hope to be a reefer soon. I am still deciding on what tank size to go with but it looks like it would be beneficial to get a water handling system set up first. I will need a RO/DI sytem that can handle between a 75 and 200 gallon tank. I have well water that is rust heavy that is run though a large rust remover as well as a large water softener. It sounds I need a large container for RO/DI fresh water for autofill and a large container for RO/DI salt water for water changes and away to get rid of wastewater. I need to get water from an utility room accessed from the garage to a basement accessed storage room to a basement finished family room. I can plumb easily from the utility room to the RO/DI system but need to get the waste water back to the utility room drain. I need to get the top off water to the reef tank, I can plumb pvc piping along the ceiling and down to the tank. Im thinking I can pump the waste water from a water change to the bathroom tub with a temporary hose and pump the replacement water to the tank with a temporary hose. Please help if you can and please feel free to dumb-it down. If you use jargon it has a good chance it will go over my head.
Spartyon
 

TheNative192

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I’d recommend going with at least a six-stage RODI system rated at around 150 GPD or higher. The additional pre-filtration stages help your DI resin last much longer by removing more contaminants before the water reaches it. That matters because the DI resin is the final “polisher” that brings the water down to 0 TDS.

TDS (Total Dissolved Solids) is basically all the unwanted minerals and contaminants in the water. The RO membrane and pre-filters in the first several stages remove most of that. The more stages you have, the more of that load is removed before it reaches the DI resin. For example the TDS may start as 250 but leave the system going into the last filter as 10 TDS. The DI resin (which is consumed as it removes TDS) then removes whatever remains — so, if 10 TDS enters the DI stage, 0 TDS should leave.

However, if too much TDS makes it to the DI stage (say 20–30+), the resin will be consumed very quickly and become expensive to replace. Think of the DI resin as a batter, once its out of juice you need to replace it or the water comes out with 10 TDS and can contaminate your tank, RODI water, & saltwater. Since you’re on a well, you may even want to consider a 7-stage system, depending on how high your source-water TDS is. A cheap handheld TDS meter from Amazon is worth having so you can check your levels.

The next big thing is GPD. GPD is simply how much RODI water the system can produce in 24 hours. For example:
  • A 150 GPD system makes ~150 gallons in 24 hours
  • That works out to about 6.25 gallons per hour
So if you’re doing a 10% weekly water change:
  • A 75-gallon tank would need roughly 1 hour of run time
  • A 200-gallon system would need closer to 3 hours
Water production also depends on your water pressure and temperature. If pressure is low, you may need a booster pump — but you won’t know that until the system is installed. Many people mount their RODI system under a sink, in a laundry room, or in a sump / utility area for easy access. Some light plumbing skills are helpful. Also some people install a system that automatically fills up with a float valve & such so you always have RODI on hand. That is definitely helpful but I do not have personal experience on that so if that interests you then I will let someone else answer that.

Water will not travel upward directly out of the RODI unit under normal conditions. Instead, most reefers:
  1. Run the RODI line into a storage container with a float valve
  2. Store the purified water there
  3. Use an ATO pump with sufficient head height to pump it up to the tank
Head height matters — some pumps can push water 10–20 feet vertically, others cannot. The exact setup depends on your room layout and how far the water needs to travel.

Most hobbyists use Brute trash cans (the food-safe / potable models) for mixing and storing RODI water and saltwater. They’re durable, widely used in the hobby, and work great with float valves and mixing pumps. Just make sure its the correct kind so it does not leach anything into the water.
 

RocketEngineer

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Running on well water, you are likely to have water pressure on the lower end of what RODI membranes prefer. While this can work, the low pressure will reduce outputs. Being on a well myself, I use an Aquatic Life Smart Buddie boost pump. Very good system that connects into the RODI unit and does several things, including the boost in pressure.

Figure out where you have access for the RODI. You want it where it’s easy to get the filters changed. Here’s mine:
IMG_2700.jpeg

I use a 5 stage system plus the Smart Buddie on the shelf.

For storing water, I use two 50g square containers. I ordered these online because they fit into the hall closet.
IMG_2702.jpeg

The blue tubing in the closet connects to the piece in the front of the tank when I’m making water. Sure, the tubing runs across the floor from the bathroom but my wife doesn’t mind.

I get water to the display using the two pumps on the floor. The one on the left is fresh, the bin on the right is for mixing salt. I just run the hose, plu in the pump, then close the hose, unplug the pump, and recoil the hose until I need it again. When my knee was messed up, my wife was able to do it.

Remember, reef keeping is as much about the water as it is the critter.

Hop this helps give you ideas.
 
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Spartyon

Spartyon

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Running on well water, you are likely to have water pressure on the lower end of what RODI membranes prefer. While this can work, the low pressure will reduce outputs. Being on a well myself, I use an Aquatic Life Smart Buddie boost pump. Very good system that connects into the RODI unit and does several things, including the boost in pressure.

Figure out where you have access for the RODI. You want it where it’s easy to get the filters changed. Here’s mine:
IMG_2700.jpeg

I use a 5 stage system plus the Smart Buddie on the shelf.

For storing water, I use two 50g square containers. I ordered these online because they fit into the hall closet.
IMG_2702.jpeg

The blue tubing in the closet connects to the piece in the front of the tank when I’m making water. Sure, the tubing runs across the floor from the bathroom but my wife doesn’t mind.

I get water to the display using the two pumps on the floor. The one on the left is fresh, the bin on the right is for mixing salt. I just run the hose, plu in the pump, then close the hose, unplug the pump, and recoil the hose until I need it again. When my knee was messed up, my wife was able to do it.

Remember, reef keeping is as much about the water as it is the critter.

Hop this helps give you ideas.
Thanks much, that helps. A special thanks for including pictures. I will have tubing running across the floor also at times including water change discharge. I was watching a UTube video and they were using an auto retrieve hose winder to help keep things tidy
 
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Spartyon

Spartyon

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I’d recommend going with at least a six-stage RODI system rated at around 150 GPD or higher. The additional pre-filtration stages help your DI resin last much longer by removing more contaminants before the water reaches it. That matters because the DI resin is the final “polisher” that brings the water down to 0 TDS.

TDS (Total Dissolved Solids) is basically all the unwanted minerals and contaminants in the water. The RO membrane and pre-filters in the first several stages remove most of that. The more stages you have, the more of that load is removed before it reaches the DI resin. For example the TDS may start as 250 but leave the system going into the last filter as 10 TDS. The DI resin (which is consumed as it removes TDS) then removes whatever remains — so, if 10 TDS enters the DI stage, 0 TDS should leave.

However, if too much TDS makes it to the DI stage (say 20–30+), the resin will be consumed very quickly and become expensive to replace. Think of the DI resin as a batter, once its out of juice you need to replace it or the water comes out with 10 TDS and can contaminate your tank, RODI water, & saltwater. Since you’re on a well, you may even want to consider a 7-stage system, depending on how high your source-water TDS is. A cheap handheld TDS meter from Amazon is worth having so you can check your levels.

The next big thing is GPD. GPD is simply how much RODI water the system can produce in 24 hours. For example:
  • A 150 GPD system makes ~150 gallons in 24 hours
  • That works out to about 6.25 gallons per hour
So if you’re doing a 10% weekly water change:
  • A 75-gallon tank would need roughly 1 hour of run time
  • A 200-gallon system would need closer to 3 hours
Water production also depends on your water pressure and temperature. If pressure is low, you may need a booster pump — but you won’t know that until the system is installed. Many people mount their RODI system under a sink, in a laundry room, or in a sump / utility area for easy access. Some light plumbing skills are helpful. Also some people install a system that automatically fills up with a float valve & such so you always have RODI on hand. That is definitely helpful but I do not have personal experience on that so if that interests you then I will let someone else answer that.

Water will not travel upward directly out of the RODI unit under normal conditions. Instead, most reefers:
  1. Run the RODI line into a storage container with a float valve
  2. Store the purified water there
  3. Use an ATO pump with sufficient head height to pump it up to the tank
Head height matters — some pumps can push water 10–20 feet vertically, others cannot. The exact setup depends on your room layout and how far the water needs to travel.

Most hobbyists use Brute trash cans (the food-safe / potable models) for mixing and storing RODI water and saltwater. They’re durable, widely used in the hobby, and work great with float valves and mixing pumps. Just make sure its the correct kind so it does not leach anything into the water.
Thanks for the helpful advice. I'm going to try to get a line run as discreetly as possible and use the ATO pump to get the top off water direct from the "pure water" tank and not have to use an ATO container which I don't have a place to stash anywhere
 

dedragon

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Thanks for the helpful advice. I'm going to try to get a line run as discreetly as possible and use the ATO pump to get the top off water direct from the "pure water" tank and not have to use an ATO container which I don't have a place to stash anywhere
easier to hide if using a dosing pump to hide the lines instead of a standard ato pump
 

RocketEngineer

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Thanks for the helpful advice. I'm going to try to get a line run as discreetly as possible and use the ATO pump to get the top off water direct from the "pure water" tank and not have to use an ATO container which I don't have a place to stash anywhere
Be careful. You do NOT want the RODI on all the time. When it’s not flowing water, the ions can migrate through the membrane. This is why you are supposed to discard the first gallon or so of water. The first gallon has all the gunk that migrated while the system was off. If you short cycle the RODI, this ends up in the tank. Instead, you want to do one long run to fill the container when it’s low/empty.

Side note, the Smart Buddie automatically discharges the first few minutes of flow to the waste line when started. It’s a really nice piece of tech.
 

RocketEngineer

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Thanks much, that helps. A special thanks for including pictures. I will have tubing running across the floor also at times including water change discharge. I was watching a UTube video and they were using an auto retrieve hose winder to help keep things tidy

My concern with something like that is saltwater comparability, especially copper compounds and greases. The devices I use are all plastic and the hose I use is meant for aquariums. Even at 25ft of hose it’s easy enough for my wife to manage.

Two things to keep in mind:
1) we maintain water, not critters. Like air, good water quality means healthier living conditions.
2) if maintenance is hard, it’s done less. Plan things to be as easy as possible and they get done more often. Life has a way of tripping us up so quick and easy lets you do it when everything else is chaos.

HTH
 

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