Yellow_donkey
New member
So I have a 60-gallon tank that is nearing 2 years old. Over the past 18 months I have strived to water change 50% once a month and have been pretty consistent with some months maybe going 45 days but over the past 6 months I have been more stringent, and have been hitting the 30 day mark. Also, my sump is a 40 breeder so with plumbing and sump and I have roughly 80 to 90 gallons of water in the system at any given time.
My RODI has worked well. I have always changed the cartridges every 6 months and a year on the membrane and watched my TDS on my DI Mix Beds.
My issue is this, 2 months ago roughly I had a water change that resulted in current brown film on the glass and a diatom bloom on the sand I must clear/cover over everyday so the tank doesn't look like crap. I am wondering with my water change regimen which worked well until just recently, am I replacing too much water in the system, resulting in what I would consider a newly cycled tank diatom breakout, but my ammonia is 0, Nitrite is 0, Nitrate is 10 and phospahte is low with use of RowAPhose and a huge cheato ball in sump.
So either I disrupted the bacterial load with too frequent and too large water changes and/or I also noticed the end of my RODI fill, 2 months ago I had a TDS of 2 to 4 at the end of the fillup of my 45 gallon Rubbermaid. I was worried but end the end went with the batch of RODI as I didnt want to waste it. This may have been a cause of my issue as well.
I ran ICP-OES a few months back on my RODI and the results were zero across the board aside for Silicon which was very high. Does this relate to silicate? The fuel source for Diatoms?
So, currently, I am fighting the daily buildup of brown on my sand and getting ready to do my next improved 40gallon water change. As I suspected the RODI may have been the culprit I have added a 10' Anion and Cation beds, priot to my original double mix bed on my rodi and after reading further saw that my muni 45 psi supply was way to low and have added a booster pump as well. So I have new batch of fresh water ready to go for another change in hope to avoid the possibility that my RODI has caused this issue but if it did, to make sure it doesn't happen again.
As a side I am loving this new RODI setup as well. Who would have known 80 psi versus 45 would have made such a huge difference. My post membrane TDS at muni supplied 45 psi was roughly 60 to 80 and that went right into my double mixed bed which depleted pretty quickly, couple water changes at the most and one 10" would need replaced.
But now with my RODI booster pump at 80 PSI I am getting 9, post membrane, 9 only, that a huge reduction by the membrane only! And that is before it ever touches any DI material. It then enters the Anion at 9 and comes out at 0, as Anion is Silicate bonding and what would grab my high Silicone levels possibly, if those two are related. In the end, my Cation and double mixed bed are all fed with 0 TDS water already (for a whole 40 gallons which prior would have depleted at least 5" of of single DI mixed bed alone)! So not only will I get super 0 water I will save a good bit of time and money on mixed bed DI replacement.
So that is the main step I have taken to try to prevent this from happening again, but I still have to fight the issue in place which will be partial sand bed removal, cleaning and reintroduction over the next couple of months.
Through this whole process and the reason for this post is my other concern that this may all be possibly due to to high a water change amount, is this to much change for the system. I also read about folks doing 90 to 100% changes and no issues for whatever reasons. But still his is nagging me.
What do you'll think. Could a 2 TDS batch of water that sneaked by me cause a diatom bloom or am I changing too much water at one time?
Also, anyone who has a post membrane TDS higher then 10, look into a booster pump, those RO membranes are supposed to run at 60 PSI or higher and they preform much better, I had no idea!
Thank everyone, look forward to thoughts or experience with slightly higher than 0 TDS tank issues?
My RODI has worked well. I have always changed the cartridges every 6 months and a year on the membrane and watched my TDS on my DI Mix Beds.
My issue is this, 2 months ago roughly I had a water change that resulted in current brown film on the glass and a diatom bloom on the sand I must clear/cover over everyday so the tank doesn't look like crap. I am wondering with my water change regimen which worked well until just recently, am I replacing too much water in the system, resulting in what I would consider a newly cycled tank diatom breakout, but my ammonia is 0, Nitrite is 0, Nitrate is 10 and phospahte is low with use of RowAPhose and a huge cheato ball in sump.
So either I disrupted the bacterial load with too frequent and too large water changes and/or I also noticed the end of my RODI fill, 2 months ago I had a TDS of 2 to 4 at the end of the fillup of my 45 gallon Rubbermaid. I was worried but end the end went with the batch of RODI as I didnt want to waste it. This may have been a cause of my issue as well.
I ran ICP-OES a few months back on my RODI and the results were zero across the board aside for Silicon which was very high. Does this relate to silicate? The fuel source for Diatoms?
So, currently, I am fighting the daily buildup of brown on my sand and getting ready to do my next improved 40gallon water change. As I suspected the RODI may have been the culprit I have added a 10' Anion and Cation beds, priot to my original double mix bed on my rodi and after reading further saw that my muni 45 psi supply was way to low and have added a booster pump as well. So I have new batch of fresh water ready to go for another change in hope to avoid the possibility that my RODI has caused this issue but if it did, to make sure it doesn't happen again.
As a side I am loving this new RODI setup as well. Who would have known 80 psi versus 45 would have made such a huge difference. My post membrane TDS at muni supplied 45 psi was roughly 60 to 80 and that went right into my double mixed bed which depleted pretty quickly, couple water changes at the most and one 10" would need replaced.
But now with my RODI booster pump at 80 PSI I am getting 9, post membrane, 9 only, that a huge reduction by the membrane only! And that is before it ever touches any DI material. It then enters the Anion at 9 and comes out at 0, as Anion is Silicate bonding and what would grab my high Silicone levels possibly, if those two are related. In the end, my Cation and double mixed bed are all fed with 0 TDS water already (for a whole 40 gallons which prior would have depleted at least 5" of of single DI mixed bed alone)! So not only will I get super 0 water I will save a good bit of time and money on mixed bed DI replacement.
So that is the main step I have taken to try to prevent this from happening again, but I still have to fight the issue in place which will be partial sand bed removal, cleaning and reintroduction over the next couple of months.
Through this whole process and the reason for this post is my other concern that this may all be possibly due to to high a water change amount, is this to much change for the system. I also read about folks doing 90 to 100% changes and no issues for whatever reasons. But still his is nagging me.
What do you'll think. Could a 2 TDS batch of water that sneaked by me cause a diatom bloom or am I changing too much water at one time?
Also, anyone who has a post membrane TDS higher then 10, look into a booster pump, those RO membranes are supposed to run at 60 PSI or higher and they preform much better, I had no idea!
Thank everyone, look forward to thoughts or experience with slightly higher than 0 TDS tank issues?