Replacing RODI

[aclman88]

I need to replace the filters and membrane for my Barricuda RODI Unit.  A little confused on what replacements to get...

 

https://www.amazon.com/gp/product/B018F55ONY/ref=ewc_pr_img_1?smid=A2ZKGRENV5NC9J&th=1

 

1. Is there a reason to get the more expensive one that's carbon+chloromines?

 

2. Anyone have other recommendations for places to buy them?  I have already checked BRS, but ala amazon is cheaper so if the ones I linked seem okay, I would just use those.

[aclman88]

[DevilDuck]

Looks like standard 10" cartridges for that model.

 

1. Check your local water treatment plant water report to see if they add chloromines to the local water. The resin will still remove chloromines but it will exhaust quicker.

 

2. Are you sure you need to replace all 3? Most of the time the sediment and carbon exhaust the quickest. Check to see if your resin filter can be refilled, it maybe most cost effective to buy resin in bulk and refill than to buy a whole new cartridge. 

 

 

[aclman88]

Thanks. Likely they need refilling s as I bought this used like three years ago

[aclman88]

9 hours ago, DevilDuck said:

Check to see if your resin filter can be refilled, it maybe most cost effective to buy resin in bulk and refill than to buy a whole new cartridge. 

Good call.  I checked this morning and it is refillable.  Do you have recommendations where to buy in bulk/where to buy sediment and carbon filters?

 

9 hours ago, DevilDuck said:

Check your local water treatment plant water report to see if they add chloromines to the local water.

Another good call.  There are about 4ppm chloramines so need to decide if I should spend more for smaller micron carbon or just let the resin handle it and plan on replacing it as needed.  I like that with the resin the color change lets you know when it is exhausted.  I think I need to set a calendar reminder to replace the sediment and carbon every 6 months.

 

I am assuming the 6 month thing is just a standard recommendation, since I am assuming it is mostly based on actual water usage.

[jservedio]

You definitely want a chloramines block with that much chloramine in the water - it'll save your membrane and your DI. The biggest worry with chlorine and chloramine is damage to the membrane, especially if the water has a high pH. You should also take a look at your report to see what the biggest issues with your water are to help choose your DI media and sediment filter. Most of the "universal" media is 50:50 anion:cation resin. However, your water makeup may make you want to change that - you don't want to be throwing out good resin just because one portion of it got depleted quickly.

 

For example, while my water is super clean compared to most, we have a decent amount of silicates - over 8ppm at all times of the year and it makes up like 10% of the total TDS. While RO is super efficient at removing silicates, that is pretty much the main ion left over after going through the RO membrane, so I lean heavy on anion resin. We also have very little  particulates in the water, so I tend to run a rougher sediment filter to keep pressure up.

 

How you set up your RODI machine should be entirely dependent on your local water source.

 

In terms of how quick you need to replace them, sediment is really easy to tell because it looks dirty and your pressure will drop. Chloramine blocks only last 2,000-2,500 gallons at 2ppm - and that's total water through them including waste water - you need to replace these a lot. Most systems are 3:1 with waste, so with 4ppm for every 250-315g of finished water, you are probably going to need to replace your carbon assuming a full 70psi - lower pressure means more waste and even more frequent carbon blocks.

[DevilDuck]

Some helpful videos:

 

 

 

 

[aclman88]

Thanks @jservedio for the breakdown.  My pressure sits around 60 psi, so I am assuming I will fall within those ranges you listed (or at least close enough).  Luckily, with a 10 gallon tank, I will not be burning through that too quickly. I figure at about 5 gallons a week between WC and top off, I should get close to a year out of them, although I may just stick with 6 months to be safe.  Here is the report https://henrico.us/assets/2021-CCR-Web-Version.pdf, it looks like chloramines are at 3ppm.

 

I was only checking my water via the inline TDS meter, which I am coming to understand is not the way to tell.  I realize now that all aspects of this unit are exhausted at this point. I pulled the resin and it is completely browned out, the sediment filter was trashed and I can only imagine the carbon and RO membrane are toast.  It could explain why the anemones I had slowly melted away while the rest of the coral were completely fine and growing... I am wondering if there were impurities getting through that was affecting them.  It might also partly explain the cyano that I have noticed starting to grow on my sinularia.  

[aclman88]

Also, since I would need a 1 micron carbon block for the chloramines, I am assuming it would be best to get 1 micron sediment filter to protect the carbon longevity?

 

Any places you recommend to purchase from?  BRS seems decent, but amazon looks cheaper overall when buying multiples of each.

[jservedio]

1 hour ago, aclman88 said:

Thanks @jservedio for the breakdown.  My pressure sits around 60 psi, so I am assuming I will fall within those ranges you listed (or at least close enough).  Luckily, with a 10 gallon tank, I will not be burning through that too quickly. I figure at about 5 gallons a week between WC and top off, I should get close to a year out of them, although I may just stick with 6 months to be safe.  Here is the report https://henrico.us/assets/2021-CCR-Web-Version.pdf, it looks like chloramines are at 3ppm.

 

I was only checking my water via the inline TDS meter, which I am coming to understand is not the way to tell.  I realize now that all aspects of this unit are exhausted at this point. I pulled the resin and it is completely browned out, the sediment filter was trashed and I can only imagine the carbon and RO membrane are toast.  It could explain why the anemones I had slowly melted away while the rest of the coral were completely fine and growing... I am wondering if there were impurities getting through that was affecting them.  It might also partly explain the cyano that I have noticed starting to grow on my sinularia.  

 

With 3ppm chloramine and 60psi, you should get right around 400 gallons of good water off a single block. I wouldn't change it at 6 months just because - I'd go by actual volume of water passing through it. No sense in throwing out good carbon blocks when they are so expensive!

 

I am just as guilty of this and let my DI media go waaaay too long. I was letting tons of Silcates into my tank even though my DI media didn't look too bad (blue anion resin was spent, yet the purple cation resin was still quite purple so it made the mixed-bed look like it still had life left in it) and it caused a ton of problems. Made my battles with hair algae go on way longer than they needed to. Even though my TDS was reading 0 both before and after the change, no more silicates were getting through and all the algae problems quickly started fading.

 

Even if your problems weren't from your RODI, I would be willing to bet it played a part. Your water report isn't super thorough, so who knows what things like phosphates, silicates, etc. look like.

 

1 hour ago, aclman88 said:

Also, since I would need a 1 micron carbon block for the chloramines, I am assuming it would be best to get 1 micron sediment filter to protect the carbon longevity?

 

Any places you recommend to purchase from?  BRS seems decent, but amazon looks cheaper overall when buying multiples of each.

The turbidity of your water is roughly 10x what mine is, so yeah, I'd probably spring for the 1 micron filters and then just change them out when your pressure gets too low. Thankfully they are cheap!

 

I get mine from BRS since I don't buy in bulk. Sediment filters and DI last at least 2 years for me, so the only thing I am changing out regularly is the carbon block every 6-8 months (I only make 500ish gallons a year, but my pressure is low so I get more than 3:1 wastewater).

[aclman88]

I was disappointed in the water report.  I'm coming from NYC and the water reporting there was incredibly detailed by comparison.  I found some on amazon with 1 micron sediment, .5 carbon and the resin for around $30 so I am just going with that for now.  I didn't realize BRS bumped their shipping minimum to $49 and I really have nothing else I need at the moment.   Thanks again for the help.  

[aclman88]

Compatible for Aquatic Life Reverse Osmosis Deionization (RODI) 10" Filter Kit (Sediment Cartridge, Carbon Cartridge, Color Indicating DI Cartridge filled with Resintech MBD-30 Nuclear Grade Resin) https://www.amazon.com/dp/B01M1VWLVK/ref=cm_sw_r_cp_api_i_2P8HZ8TKFSCJ619NRV79?_encoding=UTF8&psc=1
 

that’s the one I ended up ordering it’s priced low so I’ll just have to check the labels to make sure the micron ratings are accurate 

[aclman88]

Is it possible that replacing the resin will get the TDS back down to 1?  It is completely exhausted, so I am wondering if the membrane is still good and doesnt need to be replaced just yet.

[jservedio]

56 minutes ago, aclman88 said:

Is it possible that replacing the resin will get the TDS back down to 1?  It is completely exhausted, so I am wondering if the membrane is still good and doesnt need to be replaced just yet.

If you are getting 1ppm out of your RO membrane, it's still doing it's job really well. I certainly wouldn't think about replacing it right now. They last a really long time, and any damage done to them by chlorine and chloramine mostly happens at high pH (like 9), so unless you have really hard water, even if you were running a bad carbon block for a while, it probably didn't really do much damage if you are still getting 1ppm out of it.

 

What's your TDS out of the tap?

[aclman88]

57 minutes ago, jservedio said:

What's your TDS out of the tap?

I'm not sure.  I need to double check how my inline is wired up, since I don't know if the out tds reading is after the RO or after the DI.  

 

I also realized that as of a day or two ago, I took out the RO membrane when I cleaned/checked everything and never put it back in, so hopefully it isn't dried out.  In which case it won't matter and I will need to get another.

[aclman88]

TDS is mid 80s coming in and was 1 exiting after all stages, including DI. Just checking now and the membrane is still moist so I don’t think it completely dried out and should still be usable. I’m assuming that the resin if replaced would bring the TDS back down to zero.

[jservedio]

If you are under 10ppm coming out of the membrane after changing your sediment and carbon block, it's still good to go. What is in the water will determine how effective it is, but anything under 10ppm with your source water would be good. Talk to the nearest LFS or local reefers to see what their RO water is coming in at and that'll give you good reassurance.

 

With the same membrane I've seen anywhere between 0 tds up to almost 25 tds depending on where I lived, so as long as you are 90% or better you are in tnt expected range.

 

If you replace the membrane for any reason, make sure you get a matching restrictor or you won't make the proper pressure.

[aclman88]

Damn, right when it seems like I got the hobby at least partially figured out someone comes up and I am back to newb status. I’m looking at this unit which I have taken for granted and all the tubes, valves and connections is really throwing me for a loop at the moment. I think two kids schedule isn’t helping with the lack of mental capacity. 
 

Good call on LFS, I have a really great place about 4 minutes down the road. I’ll pick his brain. 
 

It’s a 100 gpd unit… if I replace the membrane do I have to replace the flow restrictor as well?

[jservedio]

Hah, there are just far too many facets in our ridiculous hobby.

 

You just need to match the flow restrictor to the membrane. If you replace a 100gpd with a new 100gpd you are good to go. If you currently have a 75gpd membrane and replace it with a 100gpd, you would need to get the 100gpd restrictor. They are only like $4 each, it's just anther thing to remember!

[aclman88]

Seriously, once I get a grasp on one things it turns out there is something else to learn about.  I hope the RODI stuff helps with the Cyano I am seeing; I doubt it is dinos as my phosphates are high at .66 and I am registering nitrates around 2.5. 

 

I am also hoping it might help with my nems and rhodactis. I just had a mini-maxi melt away.  The maxi was added a couple of months ago and initially did well. It disappeared under the rockwork for a couple weeks before I was able to syphon it out and put it back in light.  It was retracted, but the mouth was still closed right up until a few days ago.  It is gaping now, and I will likely remove it today when I get home from work.  A BTA was also added mid march and initially, it did well before following the same fate as the maxi that is dying now. It moved to a dark spot in the tank where it slowly shriveled and melted away over the course of a couple of weeks. The other three maxis are thankfully still doing okay, but I am pretty confident they are living on a timeline now.  My rhodactis are all alive and were growing huge and splitting like crazy up until recently.  Lately, they seem more shriveled up.  I know that mushrooms are closely related to nems, so not sure if what is affected the nems is now affecting the muchrooms.  LPS and softies are otherwise doing really well, open, and seemingly unaffected.

 

Potential theories are:

• The RODI resin and carbon block are spent, and it is possible heavy metals, contaminants or chloramines are in the ATO or mixed water.
• My nutrients are swinging (I haven't been testing regularly so not sure on this, especially since the rhodactis were doing amazing for months)
• Chemical warfare between leathers and nems.  I have three large leathers in the tank and I know leathers are known for chemical warfare.  I threw in some chemipure blue last night just in case; I have run it in the past, but I stopped a while ago.  The rhodactis were find with no chemipure, but I know they are also much hardier than nems.

I definitely need to start testing daily for alk as well since it was low a few weeks ago and last time I tested it was 12, granted this change occurred over at least 3-4 weeks and was deliberate.  

 

It turns out the RO is 100 gpd, so looks like I should be set since the old one was also 100.  I might just replace the RO membrane regardless as it is at least 4 years old and I never replaced the carbon block in over two years of use so I would assume the RO membrane would be relatively exhausted.  I will double check the TDS in and Out after replacing the sediment and carbon block.  I will post the results if you could help with deciding when to replace membrane, I am still learning about rejection rate and membrane life.

 

 

[jservedio]

Oh yeah, with .66 phosphates and only 2.5 nitrates, you are primed for a cyano outbreak sitting at 3.8:1 N:P. Any time your ratio of Nitrates to Phosphates is below 10:1, there is pressure toward cyano. Any time the ratio is over 10:1, there is pressure toward green algae. Right around 10:1 is where there is no pressure toward any specific type of algae assuming a carbon limited system. Dosing your nitrates up to 6-7ppm would definitely help with the cyano in the short term. I don't know all that much about shrooms, but rapidly fluctuating nutrients and organics are the biggest killers of nems IME. Big algae breakouts and die-offs are really rough for nems.

 

Phosphates are removed pretty well by RODI, but it really doesn't take a lot getting through to drive them up. Things like Iron and Silicates that you normally don't test for and are extremely limited in sea water are pretty abundant in drinking water systems and are probably the biggest problems from spent DI. For example, in my source water silicates are roughly 500x the concentration of seawater.

 

Changing you RODI media is pretty much the only action you can take that risks zero negative consequences, so at least it can't hurt! Definitely post up your numbers when you get them.

[aclman88]

Here are the numbers from my tds. Definitely needs replacing since the rejection rate for the membrane is 97-98%.  With the new membrane that’s being rinsed  right now is getting it down to 0. 
 

I also just bought some neonitro in case I needed to dose it, so it’s good to know about those ratios (new info to me).  I’ll see if the new rodi and water changes can bring down phos along with the chemipure I added. Thanks!

 

ps where do you get so much damn knowledge? Any particular places I should spend some time reading? 

[DevilDuck]

On 5/20/2022 at 11:02 AM, jservedio said:

Oh yeah, with .66 phosphates and only 2.5 nitrates, you are primed for a cyano outbreak sitting at 3.8:1 N:P. Any time your ratio of Nitrates to Phosphates is below 10:1, there is pressure toward cyano. Any time the ratio is over 10:1, there is pressure toward green algae. Right around 10:1 is where there is no pressure toward any specific type of algae assuming a carbon limited system. Dosing your nitrates up to 6-7ppm would definitely help with the cyano in the short term. I don't know all that much about shrooms, but rapidly fluctuating nutrients and organics are the biggest killers of nems IME. Big algae breakouts and die-offs are really rough for nems.

What?! Really?! I wish I knew this before I lost 2 BTA's. One I lost right before a dino outbreak and another the other was right after after my battle with dinos. Then I started vodka dosing and my new BTA starting declining. This piece of info needs to be framed some place!

[jservedio]

17 hours ago, aclman88 said:

Here are the numbers from my tds. Definitely needs replacing since the rejection rate for the membrane is 97-98%.  With the new membrane that’s being rinsed  right now is getting it down to 0. 
 

I also just bought some neonitro in case I needed to dose it, so it’s good to know about those ratios (new info to me).  I’ll see if the new rodi and water changes can bring down phos along with the chemipure I added. Thanks!

Getting a new membrane isn't going to hurt anything at all and with your rejection rate I'd be buying a new one too, but when you have really low TDS to begin with (70ppm is super clean, average is ~350ppm in US), your rejection rate is generally a bit lower. Keep in mind rejection rates listed on membranes all have an asterisk next to them because the contents of the source water are going to dictate how well the membrane deals with them. That said, you will probably actually see 95%+ in a new membrane. I live about 2 hours away so probably have somewhat similar water here in Raleigh with about the same TDS levels and I get 0-2ppm out of my membrane. I bet with a new one you'll do really well and it'll easily pay for itself over the next few years on how much DI media you'll be saving.

 

17 hours ago, aclman88 said:

ps where do you get so much damn knowledge? Any particular places I should spend some time reading? 

Hah! I've been at this for a pretty long time and just something that I've accumulated over the years. He hasn't been active for like 5 years, but most of what I know about RODI came from @AZDesertRat who designed, built and installed filtrations systems professionally. Generally through, if I see someone talking about something I don't understand or seems to make sense on the surface but I don't know why, I start reading through scientific papers on the subject to figure out what is true and why. Mostly, just from dealing with my own tank's problems over the last 12 years and spending hours reading about things way over my head until they start to make sense. 95% of what I know at least started from something I read here on NR that I used as a jumping off point for research.

 

 

1 hour ago, DevilDuck said:

What?! Really?! I wish I knew this before I lost 2 BTA's. One I lost right before a dino outbreak and another the other was right after after my battle with dinos. Then I started vodka dosing and my new BTA starting declining. This piece of info needs to be framed some place!

Nobody ever bothers to explain why (probably because most just parrot the advice!), but this is the reason why people suggest waiting for a tank to mature for a year before getting an anemone (particularly if using dry rock). During that first year-ish you've got rapid fire boom-bust cycles of ecological succession with all kinds of stuff going on, so your organics and nutrients are all over the place. Most inverts don't like that, but most nems are more sensitive to it than most corals. I think of stability with nutrients for keeping nems nems the same way I think of keeping alkalinity stable for acros.

[aclman88]

Good to know. I ended up replacing the membrane and was getting 0-1ppm now before putting in the new DI resin. I also did a water change with some water from my LFS replaced the old ATO water with stuff from the new unit. Alk is now 9.1, phos dropped to .12 and nitrate is now 1 so right in that 10:1 ratio, so just need to test a little more consistently and track how phos and nitrate change with my weekly water change schedule and better RO water.