Thinking about buying a rodi unit need info.

[chris124]

I get my rodi water from my lfs that might be going out of business soon so I need to start looking in to a rodi unit. My question is how long do the filters last before needing to be changed and about how much dose it cost. My water company is aqua America and its well water. The water looks clean but trust me its not. The biggest problem with aqua America is the nitrates in the water. So about how long do you think the filters would last doing a 10% water change every two weeks on a 75 gallon tank?

 

[SABOB]

I have a Buckeye Field Supply 100gpd unit, been using it for at least 5 years. Change Carbon Block and Sediment filter every 6 months and DI resin when TDS gets above 1ppm. Usually make about 30 gallons every two weeks

 

[chris124]

Ok that doesn't sound to bad thanks.

 

[ReeferEric]

Few factors you need to take into consideration:

-I assume city water, filters will last a little longer
-Filter change out are dependent on usage
-Sediment filters will tend to plug up before the carbons and Di, they should be changed every 3-6 months
-Industry standard for membranes are 75GPD

I have about 100g water volume. 1g daily automated water change, so about 30% by the end of the month. I top off a lot, maybe 3-5g a day because I use fans to force evaporate and cool the tanks. My thing is to changed sediment every 3 months and carbon 6 months. Di, I'm running a dual Di so when one is about 90% color changed, I'll change it and put the second to pass first, the new one will be the last Di before product use.

On average I will filter around 60-70g of water at a time (70g water barrel).

 

[Kworker]

I recommend Bulk reef supply RO/DI units, get one of the ones that come with the flush kit, TDS meter and all... It is definitely worth it to have that stuff. I have had my unit for over a year and a half and never changed the filter stages in the unit even though I have them. I think a major factor in that is because the TDS that comes out of the tap is 30-40TDS, Rarely it will go up to 70ish.

If you get a unit with the TDS meter it really helps. I would assume well water would have much higher TDS ratings.

 

[chris124]

That helps a lot thanks. I was thinking about getting the Brs 4 stage value plus ro/di system-75gpd and yes it is city water.

Few factors you need to take into consideration:

-I assume city water, filters will last a little longer
-Filter change out are dependent on usage
-Sediment filters will tend to plug up before the carbons and Di, they should be changed every 3-6 months
-Industry standard for membranes are 75GPD

I have about 100g water volume. 1g daily automated water change, so about 30% by the end of the month. I top off a lot, maybe 3-5g a day because I use fans to force evaporate and cool the tanks. My thing is to changed sediment every 3 months and carbon 6 months. Di, I'm running a dual Di so when one is about 90% color changed, I'll change it and put the second to pass first, the new one will be the last Di before product use.

On average I will filter around 60-70g of water at a time (70g water barrel).

 

[AZDesertRat]

Nothing compares to Spectrapure, one of the oldest names in the business with 30 years in the same US city.
They specially treat and either batch or individually test all their RO membranes to improve their performance. They are one of only a few to use 1 micron or less, near absolute rated sediment filters so they protect the billions of tiny microscopic pors in the carbon block where the chlorine is adsorbed and the only one to custom blend all their DI resins for specific uses so they last longer and work better, saving you money in the process.

Sediment and carbon block filters normally last 6 months but in ome instances that can be stretched out to 12-18 months with a little extra monitoring on your part. It is not unsuaual to see a Spectrapure RO membrane last 10 years if you keep up with the sediment and carbon replacements and annual disinfections. DI resin is dependent on how much water you make, your RO membranes efficiency and how good the resin is. Spectrapure resins last at least 33% longer than any other and usually much longer, my personal experience is I went from 150 gallons per cartridge with another wll known name brand to over 1000 gallons per cartridge with Spectrapure resin and have never looked back.

Don't waste money on flush kits, they have no proven documented value other than to lighten your wallet. For TDS meters, stick with a good handheld meter, the inlines lack the accuracy of a handheld since they are not ATC temperature compensated plus to troubleshoot a RO/DI you need 3 TDS readings, tap water, RO only and final RO/DI, most inlines only give you two of those so you need two meters. A handheld can test all three plus your ATO storage, the LFS, bottled water,your buddies water etc.

 

[Reefing Madness]

That helps a lot thanks. I was thinking about getting the Brs 4 stage value plus ro/di system-75gpd and yes it is city water.

 

[chris124]

One more thing. I don't have a spot to permanently mount the system. So what care needs to be taken when storing the unit. I read some where that the ro membrane has to stay wet.

 

[Reefing Madness]

You can't keep attached?

 

[AZDesertRat]

When using a system portable, keep water in the housings so the membrane and DI stay wet. Use the system at least every 10-14 days and try to make at least several gallons at a time to keep it well flushed. Store it in a climate controlled area like a closet or cabinet, away from temperature extremes and bright or direct lighting.

When shopping for a system compare them compoenet by component to ensure you are comparing apples to apples. Not all filters, housings, resins and fittings are the same. Look for low micron filters so they actually protect the RO membrane and make sure you get things like a capillary tube flow restrictor instead of the fixed type and an inline pressure gauge. Pass on 5 micron or larger filters, small horizontal DI filters, flush kits and dual carbons that are not needed.

 

[Jimbo662]

I'd definitely look to find a place to permanently set it up. I think you'll find it much more of a pain to have to connect it every time you need water. I make water every day for my ATO and currently do a 5 gal water change about every 3 days. I just moved into an apartment that has the laundry connections in one of those "closets" where the washer / dryer faces each other. I hung mine on the wall between the two. Put a Y connector on the washer faucet and ran the waste line down the drain.