Burning through Filters/DI Resin too fast.

[11f150]

So I moved to a new house about 2 years ago now. The water at my new house goes through filters/DI resin very fast. If I use alot of water I can use up a filter/DI in about a week and half. Is there anything I can do? I have a 4 stage BRS unit.

 

[Mark Derail]

I have a 5 stage. Mech filter and 2x carbon, then membrane then DI.

What's the input and output TDS? I got a cheap TDS meter from eBay (100+ reviews, less than 30$) and the input is around 250 tds, output 1 tds.
I've produced easily 500g or more and still getting 1 tds. I do bi-monthly 45g WCs, and evaporation 5-6g per week.

My input, I tapped the copper pipes. At first, just the cold water, and production was very low. I tap hot & cold, to double the pressure (needle piercing kits for fridge ice maker). I recombine with a Y 3/4 inch that has on/off controls, then another single on/off.

Then I put in parallel two 55g drums. When they are about halfway down, I start it up with the single on/off. That leads to a float valve. So I produce at least 50-60g in one go, instead of stop/starting smaller quantities.

HTH

 

[JoshH]

First thing is do you know what's in your source water? What's the TDS(mentioned above)? Where are you getting your water from(well or city)?

 

[tastyfish]

What's your TDS coming out of your membrane?

This is the key for preserving your DI resin and also ensuring its effectiveness. I would ensure that your membrane is operating at optimal pressure, using a pump if necessary.

Your TDS should be as close to zero as possible before hitting DI and no more than 10 (I was until single figures before running through the DI. Also ensure that you divert to waste, all water from the membrane until the TDS drops below 10.

 

[TheEngineer]

You could have high CO2. That will kill your resin in a hurry. You can do a bubble test to check. You need a pH test to do this.

Measure the pH of water straight out of the RO membrane. Fill a glass and take the water outside. Run a bubbler in it for 30 minutes and test again. If the pH goes up you have excess CO2 in the water and you need to degas it before running it into your DI.

 

[11f150]

First thing is do you know what's in your source water? What's the TDS(mentioned above)? Where are you getting your water from(well or city)?

What's your TDS coming out of your membrane?

This is the key for preserving your DI resin and also ensuring its effectiveness. I would ensure that your membrane is operating at optimal pressure, using a pump if necessary.

Your TDS should be as close to zero as possible before hitting DI and no more than 10 (I was until single figures before running through the DI. Also ensure that you divert to waste, all water from the membrane until the TDS drops below 10.

My TDS meter on the unit says "8" for in.

Source water is city. We cannot drink the water though it smells like chlorine/chemicals.

 

[KJAG]

Resin quality is critical. Have had good luck with the Spectrapure Enduro and Megamax cartridges and I have some of the most horrifying out of the tap TDS in the country here in coastal CA aside from places like Arizona. Also, assuming your ATO isn’t plumbed directly to your RODI which can rapidly burn through your DI. What’s your rejection rate for the unit and pressure to the unit itself?

 

[crayon]

Last year we moved from well water to town water. When we were on well water, we also had a water softener and a de ironizer. Didn’t change a single cartridge on our RODI in 5 years.
Now we are on town water, with no water softener and for the first year, I had a crazy algae issue in all my tanks that included being able to grow ulva algae from nothing, even though we were running a 5 stage RODI. Drove me nuts trying to pin down the issue. We thought it was nitrates, or old rock or too much food. Finally checked the RODI and realized stuff was getting through. TDS was reading 4.
We now change sediment filter cartridges every three weeks. If we stay on top of the filters, everything else is fine. However we are going to add an additional large sediment cartridge ahead of the 5 stage RODI to help with the filters.
When we get our renos done, for sure we will put a whole home softener on our place.

 

[cracker]

Sorry if I missed it ,How old is the RO membrane?

 

[11f150]

Resin quality is critical. Have had good luck with the Spectrapure Enduro and Megamax cartridges and I have some of the most horrifying out of the tap TDS in the country here in coastal CA aside from places like Arizona. Also, assuming your ATO isn’t plumbed directly to your RODI which can rapidly burn through your DI. What’s your rejection rate for the unit and pressure to the unit itself?

no I fill up the ATO container when its empty. Im not sure what the rejection rate it, its s BRS 4 stage. I have about 75 psi to it.

 

[11f150]

How old is the RO membrane?

Bought the entire unit a year ago.

 

[cracker]

Thanks for the reply, Your ro membrane could be worn out .

 

[TaylorPilot]

Like someone mentioned earlier. Check to see if you have a bunch of CO2 in the water. There isn't a way to remove it with filters. You have to take the source water, aerate it in a container, then use a low pressure pump to feed a booster pump. This is a pain and won't be cheap (probably more than the whole RODI unit) but it's the only real way to fix the problem. Next, you mentioned you have high chlorine levels. Find out if it is chlorine or Chloramine. The easiest way is to test for free chlorine, and also total chlorine. If the numbers are different, they are using chloramine. The carbon filters for chloramine are different. Finally, check the pre and post membrane TDS levels. If your rejection rate is falling off, then it will chew through DI like crazy. After you figure out about your CO2 levels, my suggestion would be to get with spectrapure. Get one of their 0.2 micron sediments, the carbon blocks required for your type of chlorine, check the membrane, and check your rejection rate to make sure that it is in the prescribed rate for your specific water hardness. This is allot of stuff, but honestly, RODI systems aren't one size fits all plug and play. Don't just throw two of their high dollar DI membranes on there till you know all the stages in front of them are working at peak performance. Also, stay away from the gradually decreasing sized filters. The smallest micron needs to be the sediment. Carbon blocks are not designed to efficiently remove solids, and will quickly become clogged. Each filter in-line has a specific purpose, and if the filter before it isn't up to the task, they will quickly become damaged or depleted. So don't get a $3 sediment filter. Get a quality .5 micron or smaller. Their .2 absolute is awesome and I have had the same one for years. My carbon blocks still don't have any tint to them yet. I can't tell you enough how much running a quality sediment that has an absolute rating LOWER than the carbon blocks will make the system work better.

 

[11f150]

Like someone mentioned earlier. Check to see if you have a bunch of CO2 in the water. There isn't a way to remove it with filters. You have to take the source water, aerate it in a container, then use a low pressure pump to feed a booster pump. This is a pain and won't be cheap (probably more than the whole RODI unit) but it's the only real way to fix the problem. Next, you mentioned you have high chlorine levels. Find out if it is chlorine or Chloramine. The easiest way is to test for free chlorine, and also total chlorine. If the numbers are different, they are using chloramine. The carbon filters for chloramine are different. Finally, check the pre and post membrane TDS levels. If your rejection rate is falling off, then it will chew through DI like crazy. After you figure out about your CO2 levels, my suggestion would be to get with spectrapure. Get one of their 0.2 micron sediments, the carbon blocks required for your type of chlorine, check the membrane, and check your rejection rate to make sure that it is in the prescribed rate for your specific water hardness. This is allot of stuff, but honestly, RODI systems aren't one size fits all plug and play. Don't just throw two of their high dollar DI membranes on there till you know all the stages in front of them are working at peak performance. Also, stay away from the gradually decreasing sized filters. The smallest micron needs to be the sediment. Carbon blocks are not designed to efficiently remove solids, and will quickly become clogged. Each filter in-line has a specific purpose, and if the filter before it isn't up to the task, they will quickly become damaged or depleted. So don't get a $3 sediment filter. Get a quality .5 micron or smaller. Their .2 absolute is awesome and I have had the same one for years. My carbon blocks still don't have any tint to them yet. I can't tell you enough how much running a quality sediment that has an absolute rating LOWER than the carbon blocks will make the system work better.

Thank you for your reply. I called the water company before I bought he RODI unit to see if there is Chloramine and they said no. But Ill have some work to do to see whats going on.

 

[drawman]

You could have high CO2. That will kill your resin in a hurry. You can do a bubble test to check. You need a pH test to do this.

Measure the pH of water straight out of the RO membrane. Fill a glass and take the water outside. Run a bubbler in it for 30 minutes and test again. If the pH goes up you have excess CO2 in the water and you need to degas it before running it into your DI.

Like someone mentioned earlier. Check to see if you have a bunch of CO2 in the water. There isn't a way to remove it with filters. You have to take the source water, aerate it in a container, then use a low pressure pump to feed a booster pump. This is a pain and won't be cheap (probably more than the whole RODI unit) but it's the only real way to fix the problem. Next, you mentioned you have high chlorine levels. Find out if it is chlorine or Chloramine. The easiest way is to test for free chlorine, and also total chlorine. If the numbers are different, they are using chloramine. The carbon filters for chloramine are different. Finally, check the pre and post membrane TDS levels. If your rejection rate is falling off, then it will chew through DI like crazy. After you figure out about your CO2 levels, my suggestion would be to get with spectrapure. Get one of their 0.2 micron sediments, the carbon blocks required for your type of chlorine, check the membrane, and check your rejection rate to make sure that it is in the prescribed rate for your specific water hardness. This is allot of stuff, but honestly, RODI systems aren't one size fits all plug and play. Don't just throw two of their high dollar DI membranes on there till you know all the stages in front of them are working at peak performance. Also, stay away from the gradually decreasing sized filters. The smallest micron needs to be the sediment. Carbon blocks are not designed to efficiently remove solids, and will quickly become clogged. Each filter in-line has a specific purpose, and if the filter before it isn't up to the task, they will quickly become damaged or depleted. So don't get a $3 sediment filter. Get a quality .5 micron or smaller. Their .2 absolute is awesome and I have had the same one for years. My carbon blocks still don't have any tint to them yet. I can't tell you enough how much running a quality sediment that has an absolute rating LOWER than the carbon blocks will make the system work better.

+3 on the CO2. I have the same issues with one of my RODI units and I burn through resin very quickly. If you want to do anything about it you will need to degass the water before it reaches the DI which will require a more elaborate setup. Personally, I choose to live with the higher cost of replacing DI resin.

 

[TheEngineer]

A degassing setup is under $20. I do this for my water. It’s just a bucket with an air stone in it. I then gravity feed that through my DI into a second bucket.

It’s an extra step and adds time to the process but to say it is expensive or not worth doing because of the effort is simply wrong.

 

[TaylorPilot]

Ideally, you want to operate the degassing before the RO. The problem with doing it afterwards is that the air being pushed through the 1-2 TDS post ro water will introduce dirt back into the water rising the TDS, making the DI burn through faster. Think Rainbow vacuum cleaners. They work just the same. The problem with doing it before is that you need two pumps. A low pressure feed pump, and a higher pressure booster pump. It is the optimal setup but not cheap. I'd be curious to see the actual rise in TDS of using un-filtered air. Maybe an in-line air filter on the air pump would fix it. @TheEngineer have you ever tested the water before and after the air pump but before the DI?

 

[KJAG]

Something else noteworthy is softening your water( if you have hard water) prior to your system. I have hard water in my municipal tap and added a portable water softener which has drastically increased the efficiency/ life of my system( as an aside I have quick disconnect valves on it so I can rinse my car with it and then use DI for the final rinse which leaves no water spots on the vehicles , but I digress) Something to consider if you have hard water. I would personally never run my RODI system without it. I don’t have time to get into the details of water softeners and RODI but you can google the benefits.

 

[TheEngineer]

Ideally, you want to operate the degassing before the RO. The problem with doing it afterwards is that the air being pushed through the 1-2 TDS post ro water will introduce dirt back into the water rising the TDS, making the DI burn through faster. Think Rainbow vacuum cleaners. They work just the same. The problem with doing it before is that you need two pumps. A low pressure feed pump, and a higher pressure booster pump. It is the optimal setup but not cheap. I'd be curious to see the actual rise in TDS of using un-filtered air. Maybe an in-line air filter on the air pump would fix it. @TheEngineer have you ever tested the water before and after the air pump but before the DI?

I test out of the RO into the bucket and then out of the bucket into the DI and finally out of the DI. There is zero change in TDS after degassing. There are no pumps needed for this process. Gravity does all the work.

I went from getting maybe 40 gallons per DI cartridge to now getting hundreds of gallons. Even if aerating added a couple TDS, which I do not believe to be true and in my experience is not true, you’re talking about an insignificant amount and could maybe cost you a few gallons total per cartridge. Far less than the cost of any filtering over the lifetime of the system.

 

[tastyfish]

My TDS meter on the unit says "8" for in.

Source water is city. We cannot drink the water though it smells like chlorine/chemicals.

Oh that's interesting, although I note you had already checked if they are adding chloramine... Are they adding flourine to the water?

Are you running a carbon block as one of your pre-filter stages? My TDS is typically between 4-7 post membrane after settling down (I live in a high chalk/limestone area with very hard water, TDS at tap is typically 380+).

When you start up your RO, do you divert the firt 5 minutes of production RO to waste, bypassing the DI pods? I do this and it really helps save your resin. (I wait until TDS reads <7 post membrane before diverting to DI pods).

I use a decent quality mixed bed DI resin from Tulsion which works very well and doesn't carry a premium price.