Miami Reef
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What levels are the phosphate?
Silicon / Silicates in RODI water
- Thread starter wazupjames
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FernBluffReef
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Curious what an unacceptable level of Silicon really is then???
I ask as I just got my ICP back today and this thread is recent. I hope its ok if I pile on.
My RO/DI was flagged as critically high @ 1,643 ug/l. The tank on the other hand was rated as near nature 189.3 ug/l which is a bit higher then said to be ideal @ 103 ug/l
My prior ICP last June. The RO/DI was 0 ug/l and the tank was 144 ug/l so not really all that much different.
I do have some what appear to be diatom growth in the tank on the sand bed. I don't usually vacuum the bed, and my diamond goby jumped a while back so I blamed on me being busy and neglecting the sand bed vs. anything else...
I have not changed media. I am on well water but really good water (much better than any city water I've been on:-). I have a seven stage BRS. The Cation looks brand new. The Anion looks to be maybe 1/4 depleted. The mixed resin looks brand new. The ICP says to replace the resin. Silicon was the only element detected by the ICP, the rest were all N/D
Changes made - since the last test in June - is I fairly recently installed an RO Buddy to increase pressure and as a result the volume of water produced. It's my understanding that the increased pressure improves the performance of the RO membrane, and the resin performance should be unaffected. The only other difference is this test I was lazy and I grabbed the RO/DI sample out of a five-gallon bucket I have in the house vs. direct from the RO/DI storage over in my shop. I use those same buckets for water changes, etc. but they are generally wiped dry before filling with RO/DI. I only stage some in RO in buckets in the house so its warmer when filling my ATO reservoir. My mixing station is out in my shop, which I generally do not heat, and that would be the other difference... the last ICP was taken in summer so probably ~70 in the shop vs. winter so probably mid-40s in the shop.
So my question.
1) I'm not sure if I should believe the RO/DI 1,643 Silicon number as it seems a stark difference, but I only have two tests to go on. Potential contamination sources? I know RO will change PH when exposed to air, etc. but not Silicon? Can't imagine storing it in my water change buckets contributed that much? Can the resin be depleted that much and show little visible evidence of
2) I believe I should replace the Anion resin - I have a pouch of Anion resin on-hand as it's the only resin I've seen any amount of depletion, or should I replace all seven filters - I also have a full set of filters on hand for when needed. I've not change either as again the only media having any visible color change is the Anion and its only ~25% the way up the cartridge and the mixed bed after that has no visible depletion.
I ask as I just got my ICP back today and this thread is recent. I hope its ok if I pile on.
My RO/DI was flagged as critically high @ 1,643 ug/l. The tank on the other hand was rated as near nature 189.3 ug/l which is a bit higher then said to be ideal @ 103 ug/l
My prior ICP last June. The RO/DI was 0 ug/l and the tank was 144 ug/l so not really all that much different.
I do have some what appear to be diatom growth in the tank on the sand bed. I don't usually vacuum the bed, and my diamond goby jumped a while back so I blamed on me being busy and neglecting the sand bed vs. anything else...
I have not changed media. I am on well water but really good water (much better than any city water I've been on:-). I have a seven stage BRS. The Cation looks brand new. The Anion looks to be maybe 1/4 depleted. The mixed resin looks brand new. The ICP says to replace the resin. Silicon was the only element detected by the ICP, the rest were all N/D
Changes made - since the last test in June - is I fairly recently installed an RO Buddy to increase pressure and as a result the volume of water produced. It's my understanding that the increased pressure improves the performance of the RO membrane, and the resin performance should be unaffected. The only other difference is this test I was lazy and I grabbed the RO/DI sample out of a five-gallon bucket I have in the house vs. direct from the RO/DI storage over in my shop. I use those same buckets for water changes, etc. but they are generally wiped dry before filling with RO/DI. I only stage some in RO in buckets in the house so its warmer when filling my ATO reservoir. My mixing station is out in my shop, which I generally do not heat, and that would be the other difference... the last ICP was taken in summer so probably ~70 in the shop vs. winter so probably mid-40s in the shop.
So my question.
1) I'm not sure if I should believe the RO/DI 1,643 Silicon number as it seems a stark difference, but I only have two tests to go on. Potential contamination sources? I know RO will change PH when exposed to air, etc. but not Silicon? Can't imagine storing it in my water change buckets contributed that much? Can the resin be depleted that much and show little visible evidence of
2) I believe I should replace the Anion resin - I have a pouch of Anion resin on-hand as it's the only resin I've seen any amount of depletion, or should I replace all seven filters - I also have a full set of filters on hand for when needed. I've not change either as again the only media having any visible color change is the Anion and its only ~25% the way up the cartridge and the mixed bed after that has no visible depletion.
Randy Holmes-Farley
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Silicate is typically rapidly consumed in a reef tank. I regularly dosed it.
No level in ro/di is too high unless you have a problematic level of diatoms.
If you do have excessive diatoms, a better di may be in order. I don’t think your levels are consistent with 0 ppm tds. What else was in the ro/di? Sodium? Calcium? Chloride?
But in any case, a second mixed di will reduce it. Maybe a new anion resin.
No level in ro/di is too high unless you have a problematic level of diatoms.
If you do have excessive diatoms, a better di may be in order. I don’t think your levels are consistent with 0 ppm tds. What else was in the ro/di? Sodium? Calcium? Chloride?
But in any case, a second mixed di will reduce it. Maybe a new anion resin.
FernBluffReef
Active Member
Out of the membrane, TDS is 1. Out of the cation and anion the TDS is zero going into the mixed bed and of course still zero after the mixed bed. The only thing detected in the RO/DI water was Silicon. aka triple TDS sensors
Attached is the full report. RO/DI is page 4 & 5
I will plan on replacing the Anion
Randy Holmes-Farley
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Partner Member 2027
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My Tank Thread
Ok, they did not test the common ones in the ro/di, such as sodium. :)
FernBluffReef
Active Member
Yes, it's interesting the ICP does not test for sodium in the RO/DI water
That said, another data point or two is
1) I am on well water. It is a community well and I manage the well
2) Although a small community system, we none-the-less are heavily regulated by the state and the EPA as if we are municipal water system - expensive and a pain - so I have to get all sorts of testing done for compliance reasons. But on the other hand, I know more about what's in my water than most do, and I know it's safe for me and my family and that it is better water than most in the country. We are very lucky and happen to have a very good source, we do not have to treat the water at all, etc. etc etc. - knock on wood, Murphy please don't strike
3) Untreated water from the well - sodium is < 5 mg/l. This is from a state certified drinking water lab perspective "not detectable". So, to your question on sodium content, it is not measurable at the source per state and EPA certified lab (Drinking water IOC test panel IOC - Complete Inorganic Analysis). Further detail: Mg out of the well is 8.4 mg/l. CA is a bit higher 18 mg/l. Total Nitrate 1.2. It's not real hard water, moderate - 80 mg/l. Conductivity is 160 umhos/cm, turbidity <.1 NTU. TDS out of my RO filter usually runs @ 1 TDS and I almost always flush the lines well before anything hits the DI
It's quite interesting, to me anyway, that the anion resin only visibly showed ~20% spent and the mixed bed that followed the anion still looked 100% brand new.
I'm currently of the mind that the ICP either screwed up or the sample somehow got contaminated as the silicon in my tank were measured at about 1/9th of that of the ICP for the RO/DI and the tank water did not test all that much higher than the last ICP when the RO/DI water had measured ND on silicon.
Either way to be safe, I went ahead and changed all the filters (save the RO membrane). Cheap insurance given the current filters were about 18 months old and had probably 1,500 or so gallons thru them. But again, the sediment filter wasn't even dirty yet, the TDS out of the RO was only two at the time and only the anion showed some evidence of depletion - maybe 20% up from the bottom.
If the ICP was right, it makes me wonder if there is something that depletes in a manner that the resin would not show but given my understanding of how the chemistry works (which is limited) I would not think that to be the case? The only real change I had made is about 3-4 months ago I installed a RO Buddy booster increasing the source water pressure from an average of 50PSI to 90-100PSI but its my understanding that should only increase the effectiveness of the RO.....
Interesting indeed. I'll be very curious what my next ICP on the RO/DI will say, maybe more interested that what is says about my tanks water LoL
That said, another data point or two is
1) I am on well water. It is a community well and I manage the well
2) Although a small community system, we none-the-less are heavily regulated by the state and the EPA as if we are municipal water system - expensive and a pain - so I have to get all sorts of testing done for compliance reasons. But on the other hand, I know more about what's in my water than most do, and I know it's safe for me and my family and that it is better water than most in the country. We are very lucky and happen to have a very good source, we do not have to treat the water at all, etc. etc etc. - knock on wood, Murphy please don't strike
3) Untreated water from the well - sodium is < 5 mg/l. This is from a state certified drinking water lab perspective "not detectable". So, to your question on sodium content, it is not measurable at the source per state and EPA certified lab (Drinking water IOC test panel IOC - Complete Inorganic Analysis). Further detail: Mg out of the well is 8.4 mg/l. CA is a bit higher 18 mg/l. Total Nitrate 1.2. It's not real hard water, moderate - 80 mg/l. Conductivity is 160 umhos/cm, turbidity <.1 NTU. TDS out of my RO filter usually runs @ 1 TDS and I almost always flush the lines well before anything hits the DI
It's quite interesting, to me anyway, that the anion resin only visibly showed ~20% spent and the mixed bed that followed the anion still looked 100% brand new.
I'm currently of the mind that the ICP either screwed up or the sample somehow got contaminated as the silicon in my tank were measured at about 1/9th of that of the ICP for the RO/DI and the tank water did not test all that much higher than the last ICP when the RO/DI water had measured ND on silicon.
Either way to be safe, I went ahead and changed all the filters (save the RO membrane). Cheap insurance given the current filters were about 18 months old and had probably 1,500 or so gallons thru them. But again, the sediment filter wasn't even dirty yet, the TDS out of the RO was only two at the time and only the anion showed some evidence of depletion - maybe 20% up from the bottom.
If the ICP was right, it makes me wonder if there is something that depletes in a manner that the resin would not show but given my understanding of how the chemistry works (which is limited) I would not think that to be the case? The only real change I had made is about 3-4 months ago I installed a RO Buddy booster increasing the source water pressure from an average of 50PSI to 90-100PSI but its my understanding that should only increase the effectiveness of the RO.....
Interesting indeed. I'll be very curious what my next ICP on the RO/DI will say, maybe more interested that what is says about my tanks water LoL
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