Sorry, long post
Problem - I have been fighting diatoms for 3.5 years in a acrylic 150 gallon mixed reef. Spectrapure RO system. I am on city water.
The tank has been set up since June , 2017. It was started with BRS Pukani dry rock. The rock stayed in saltwater with a powerhead for 5 months with water changes until p04 dropped below .04.
Current parameters: CA 400(Red Sea ) Alk 8.4 (Hanna) salinity 1.026 (refractometer) PH 8.15 ( Salifert) p04 .034 (Hanna) nitrate 5 (Salifert) Mag 1335 (Salifert)
Salt ESV
2 part ESV
Fish food fed: frozen Larry’s Reef Frenzy & PE Mysis, dry Sustainable Aquatics Hatchery Diet and New Life Spectrum small fish formula
Diatoms (verified by a microscope) will not go away. They are on the sand, glass & powerheads. I purchased a Seachem Silicate test kit and checked: incoming tap water, RO out water, RO storage barrel water, the tests showed so low on the scale it is hard to see a change in the color.
I replaced RO filters including adding a Silica Buster followed by a mixed bed, it might have helped for a very short time so I yanked those out and added a cation followed by anion followed by a mixed bed. Diatoms persisted.
I pulled out a cup of substrate out and let it sit in fresh saltwater overnight. Seachem test showed 4. It must be coming from the substrate!
I vacuumed out all 150 pounds and replaced it with Caribsea Special grade aragonite that had been rinsed until the water ran clear. The rinsing took 3 hours. 1 week later the diatoms were back.
I emailed and discussed the issue with Spectrapure. They suggested I purchase a Com-100 TDS meter and check everything. That done, RO output is .06 however my RO storage barrel registered a whopping 438! The barrels came from a manufacturer locally that makes new and refurbishes and cleans used. I purchased used but did not ask what they previously held, my mistake. I assumed they were food grade.It had to be the barrels!!
I then ripped out my entire RO storage and saltwater mixing barrels and replaced them with 2, 32 gallon Brute food grade containers which were scrubbed out with vinegar & water. All stored RO, saltwater and top off water was dumped. Slowly the diatoms have returned. Stored water in the Brute container reads .06.
Unless silicates are leaching out of the rocks I am out of ideas.
Any suggestions?
Thanks.
Problem - I have been fighting diatoms for 3.5 years in a acrylic 150 gallon mixed reef. Spectrapure RO system. I am on city water.
The tank has been set up since June , 2017. It was started with BRS Pukani dry rock. The rock stayed in saltwater with a powerhead for 5 months with water changes until p04 dropped below .04.
Current parameters: CA 400(Red Sea ) Alk 8.4 (Hanna) salinity 1.026 (refractometer) PH 8.15 ( Salifert) p04 .034 (Hanna) nitrate 5 (Salifert) Mag 1335 (Salifert)
Salt ESV
2 part ESV
Fish food fed: frozen Larry’s Reef Frenzy & PE Mysis, dry Sustainable Aquatics Hatchery Diet and New Life Spectrum small fish formula
Diatoms (verified by a microscope) will not go away. They are on the sand, glass & powerheads. I purchased a Seachem Silicate test kit and checked: incoming tap water, RO out water, RO storage barrel water, the tests showed so low on the scale it is hard to see a change in the color.
I replaced RO filters including adding a Silica Buster followed by a mixed bed, it might have helped for a very short time so I yanked those out and added a cation followed by anion followed by a mixed bed. Diatoms persisted.
I pulled out a cup of substrate out and let it sit in fresh saltwater overnight. Seachem test showed 4. It must be coming from the substrate!
I vacuumed out all 150 pounds and replaced it with Caribsea Special grade aragonite that had been rinsed until the water ran clear. The rinsing took 3 hours. 1 week later the diatoms were back.
I emailed and discussed the issue with Spectrapure. They suggested I purchase a Com-100 TDS meter and check everything. That done, RO output is .06 however my RO storage barrel registered a whopping 438! The barrels came from a manufacturer locally that makes new and refurbishes and cleans used. I purchased used but did not ask what they previously held, my mistake. I assumed they were food grade.It had to be the barrels!!
I then ripped out my entire RO storage and saltwater mixing barrels and replaced them with 2, 32 gallon Brute food grade containers which were scrubbed out with vinegar & water. All stored RO, saltwater and top off water was dumped. Slowly the diatoms have returned. Stored water in the Brute container reads .06.
Unless silicates are leaching out of the rocks I am out of ideas.
Any suggestions?
Thanks.
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