Persistent Diatoms, need help!

[Stingray122]

Hi. I am having a persistent diatom problem. It grows mostly on the rocks, in thick beds that grow back within a few days of removal. My water change schedule is 25% change per week. I use RO/DI water always at 0 TDS, after being ran through two DI canisters. I am on well water that tests around 300ppm, drops to 14 after RO membrane. I have been scrubbing the rocks with a toothbrush every 3-4 days, then changing filter sock immediately after, along with skimming very wet. The organism in question will grow back overnight, and completely cover the rocks within a week, especially where lighting is most intense near surface of water.

I have tried using Dr. Tim's Waste away for about a month, never saw any improvement. Skimmer was always off for 2 days following bacterial dose, along with running no filter socks as the first time I dosed it, all of the bacteria grew in there (white strings galore). I have also tried running GFO, never seem to see any improvement either. I am just dumbfounded at the cause of these diatoms. I cant seem to put my head around if its too nutrient-rich in my tank, or nutrient-lacking. My refugium never grows , I have yet to have to remove any of it for space during the 9-month period this tank has been up. I have been taking it very slow, as I am in school. I plan on adding a royal gamma soon, along with a cleaner shrimp, a few more snails, and a few hermits in the next month. I have 11 frags in my QT tank doing excellent right now, although the ones in my display look like hell in a handbasket. Not too worried about them, as they were my first corals and I expected it, but would like to keep these new ones looking great. The QT tank has been testing around 5 nitrate, 0 phosphate, which is where I'd like to get my current display as well. Looking for some expertise that people on this site always have, looking for cause and treatment.

I have nitrate (Neonitro by brightwell) available to dose, along with phosphate (Seachem Flourish). Just received some Microbacter7 as well. Like I said before, just looking for some guidance! Look forward to hearing from you guys. Ive researched for hours, and everybody seems to say run GFO, or dose bacteria, both of which just didn't seem to work for me. Water changes, no matter how large, don't prevent this from growing back. Thanks again in advance! Information on tank follows:

System info:
40 gallon breeder
Trigger System 30in Sump (17ish gallons)
Maxspec Razor 24in 160W LEDs
Reef Octopus INT-110 Skimmer
Kessil H160 Tuna Flora Refugium Light (Ran from 10pm to 6am, growing chateomorpha)
Mp10 QD at half power running Reef Crest
Maxspec Gyre 1k at 80% power running Pulse
2x 100W Eheim Jager
Tunze Osmolator (not running any kalk or dosing)
Neptune Apex Classic
Red Sea Blue Bucket

Parameters:
Temperature: locked in at 78.1-78.2 degrees via Apex
pH: 7.95 (night) and 8.10ish (Day)
Salinity: 1.025 (Refractometer)
Alkalinity: 8.1 (Red Sea Alk Pro)
Calcium: 420ppm (Red Sea)
Mag: Have not tested, will if needed in assisting me
Phosphate: Undetectable (NYOS kit)
Nitrate: Undetectable (NYOS kit)

I am not dosing, thinking I will start as the pH of my tank goes to about 8.2 after a WC but drops rather quickly.

Bioload:
Two Clownfish
1 Torch Coral
5 SPS (that don't look to well, one bounced back very well)
2 Trochus snails

Photo:

 

[saltyfilmfolks]

Are you running a single or dual Di resin canister?

Silicate will or can slip by the resins.

Gfo will pull the silicate , but with low Po4 you might not want that.

 

[Stingray122]

Two single canisters with mixed bed. Always changed when near the top. Always tests at 0, second canister is always blue the whole way through.

Edit: RODI water has been used from the start of the tank as well, never have used my well water, as I live in a farm heavy area I'm sure nitrates are crazy high. Maybe that's what I need right now though xD

 

[saltyfilmfolks]

The first di can is burned ?

 

[Stingray122]

Oh and I tried the overfeeding thing for like a month, still grew at the same rate, nitrates were still 0 and phosphates still 0.. I think my refugium just sucks it out overnight so fast. But, my water has a kind of strange smell to it when I don't run carbon. Definitely coming from these diatoms as when the rock gets exposed during a water change it has the same exact scent. Is my best bet to try and increase nutrients? Forgot to mention a key thing everyone always talks about during their cycle. I have never had a speck of green hair algae grow in the display, I've had a light dusting on the refugium acrylic though. My lighting schedule on the Maxspec Razor is as follows:

10am: 0W OB
noon: 0W 30B
2pm 25W 60B
6pm: 25W 60B
8pm: 0W 30B
10pm: 0W 0B

 

[Stingray122]

The first di can is burned ?

No I always change the first can when it reaches about 1.5inches from the top of brown. Second can is always completely blue (brand new), I use it as a safety measure. I check it regularly when I'm making water. I do burn through resin like mad, but attribute it to my well water having high CO2 content, as my membrane outputs about 14-16ppm consistently.

 

[saltyfilmfolks]

Diatoms are driven by the presence of silicate. To a small extent nitrogen and phosphorus.
If it’s diatom I don’t belive nutrients are the issue.

Randy F actually has a great Article on dosing silicate as a means to combat other algaes.

Interesting case.

 

[Stingray122]

Is GFO the only way to remove silicates? I'd hate to keep my phosphate lower than undetectable.. I am running about 3/4 cup as we speak though, as this is becoming a frustrating nightmare. I am not ready to give up though, enjoying this hobby too much, and half the fun is learning more and the entire experience.

 

[saltyfilmfolks]

I was looking for other options to remove silicate a second ago. Most so far like chemipure remove Po4 too.

I’m wondering if it’s possible to treat the water instead.

Also cuc snails , sponges and other out of the box thoughts.

#reefsquad

 

[Stingray122]

Also to mention, I am going to school to be a Medical Lab Tech, so I do have microscopes, dyes, and other things available to me if we are questioning if these are diatoms or not! Although the microscopes do not have picture taking ability, I could draw out what I saw, as I would have no idea what I am looking at!

 

[Jason mack]

I took photos through the microscope with my phone ..works well enough ..

 

[Stingray122]

I took photos through the microscope with my phone ..works well enough ..

Definitely can give that a try tomorrow, I will bring a sample with me to class.

 

[miyags]

I think BRS has some DI resin that removes silicates.

 

[CMO]

Sounds like it could be dinos to me. Your noting of undetectable NO3 and PO4 also supports that suspicion. I'd get a sample under the microscope asap and you can take a pic with a phone camera through the scope. I had what I thought were diatoms for some 5 months before confirming dinos with a scope.

 

[Stingray122]

Sounds like it could be dinos to me. Your noting of undetectable NO3 and PO4 also supports that suspicion. I'd get a sample under the microscope asap and you can take a pic with a phone camera through the scope. I had what I thought were diatoms for some 5 months before confirming dinos with a scope.

Will do. Difficult to do it by eye it seems, never seen the characteristic trapped air bubble, that what made me lean more towards diatoms. Microscope will be only definitive answer, should have done it sooner.

 

[Jason mack]

I'm also leaning towards Dinos ...but there are so many strains ..ID definitely needed ..

 

[Stingray122]

Will be taking a sample along tomorrow, just trying to find a razor blade at the moment to remove some, as it is difficult to remove from the rocks without scraping.

 

[CMO]

Will do. Difficult to do it by eye it seems, never seen the characteristic trapped air bubble, that what made me lean more towards diatoms. Microscope will be only definitive answer, should have done it sooner.

Yeah some strains such as amphidinium (which is what I had) don't have a ton of bubbles, especially in mild cases like mine had almost none.

 

[rkpetersen]

Only relevant if this turns out to be diatoms, I guess. Anyway I always had a trace of silicon getting through into my rodi water, sometimes with a bit of something else, on multiple ICP-OES tests over the last couple of years, until I replaced the second regular mixed bed DI cartridge with a Spectrapure silicabuster. I sent two separate samples to ATI in November and for the first time there were undetectable levels of everything, including silicon. Pretty impressive.

 

[Stingray122]

Yeah some strains such as amphidinium (which is what I had) don't have a ton of bubbles, especially in mild cases like mine had almost none.

Is it that easy to identify strains just based on microscopic characteristics? Or do you need to use any stains or special procedures? I am familiar with looking for motility, so I will mount the slide expecting that.