Never-ending diatoms

[Renan Isse]

Hey, guys, I'm a reefer from Brazil. My 300L tank is one and a half year old and I can't get rid of these goddam brown stuff on my sandbed. I've tried almost everything to remove these algae and nothing seems to work. I use natural sea water for water changes, but every now and then, when it's necessary, i mix my own water using RODI and aquaforest reef salt. I used to start NSW to lessen the cost of salt and also because it helped me once to get rid of these algae for one month or so.
I'm running GFO (Phosphate Minus from Aquaforest) to keep PO4 levels steady at 0.03 (readings from salifert test). My silicate levels are very low (0,03), and I make sure by testing my RODI water with salifert silicate test as well. Nitrate is not an issue, since they vary from 2 to 5. The other params are steady, within the recommended for reeftanks.
Lights are on for 8 hours a day, of which 2 hours are only in blue lights. Flow (2 jebao RW8) is also okay, since it can't be to strong, due to my tank being a LPS reef.
Even though I'm facing this scenario, All my fish and corals are fine.

Any thoughts?

 

[nautical_nathaniel]

Are you able to post any pictures? We need to first make sure it is diatoms and not something else.

 

[HolisticBear]

Diatoms typically feed on silicates, once the silicates are exhausted they disappear. So something is refreshing the silicates (usually the water). A good RODI (remembering to replace filters) should remove them.

My fear is that your dealing with Dinos and not Diatoms. Pictures will help people id

 

[brandon429]

in nanos, the issue is non existent when they pre rinse the sandbed before use, harshly, and then maybe once or twice during and after cycling. that removes silicates/prime fuel, it physically removes the invader to the point it cannot sustain, and in the tanks I manage online we literally have zero uglies phase or diatoms at any time. with a large tank, creatively getting at it physically is tough, although UV can solve that easily if done right. the more we can physically access the sandbed and the substrates, the easier it is to never have that phase. only hands off systems have enduring invasions that are not anchored in some way, actively cleaned ones wont. handy info should that option ever arise during a move or something, some access point the tank doesn't normally see.

there are grazers for that invader on a real reef, they're missing here, that's the issue. Even with silicates, the right grazers wouldn't allow that to sustain. cheat grazing (deep cleaning) is a handy option where available. once we start clean a few times, the tanks run uninvaded the rest of the time given decent QT and cleaning runs as commanded by the tank.

I know of a thread here where a dinos invasion lasted over 24 months straight, all manner of treatment was tried just shy of actual cleaning. they can be ornery in some cases

 

[Renan Isse]

Sorry, I forgot the pictures. Here they are. I believe it's not silicates, because they read 0.03 according to my salifert test, in my RODI water. Also, since I'm running GFO, it should also reduce the silicates in the tank.

 

[Renan Isse]

in nanos, the issue is non existent when they pre rinse the sandbed before use, harshly, and then maybe once or twice during and after cycling. that removes silicates/prime fuel, it physically removes the invader to the point it cannot sustain, and in the tanks I manage online we literally have zero uglies phase or diatoms at any time. with a large tank, creatively getting at it physically is tough, although UV can solve that easily if done right. the more we can physically access the sandbed and the substrates, the easier it is to never have that phase. only hands off systems have enduring invasions that are not anchored in some way, actively cleaned ones wont. handy info should that option ever arise during a move or something, some access point the tank doesn't normally see.

there are grazers for that invader on a real reef, they're missing here, that's the issue. Even with silicates, the right grazers wouldn't allow that to sustain. cheat grazing (deep cleaning) is a handy option where available. once we start clean a few times, the tanks run uninvaded the rest of the time given decent QT and cleaning runs as commanded by the tank.

I know of a thread here where a dinos invasion lasted over 24 months straight, all manner of treatment was tried just shy of actual cleaning. they can be ornery in some cases

I also vacuum the sand bed in every water change I do. I remove lots of detritus, but day after day, as soon as I finish the husbandry, within 4 hours or so, the sand is filled with brown ugly stuff! At some point, I thought that reducing the nutrient levels, I'd not have this problem anymore, but that seems to not be happening. I don't use CUC because my melanurus feeds on them and I also believe that what they eat, they poop back, which makes me vaccum to clean the sand.

 

[brandon429]

I know this sounds like a broken clock referral from me but I would never ever own a reef above 50 gallons without a UV sterilizer for the very challenges you see here, but mostly for those dinos once they get in.

UV isn't required for good reefing, its just the handiest cheat a large tanker could ever own that wont hurt your corals to try. all other methods of control sure do affect corals (but not rip cleaning) and still fail at times.

that's tank wrecking risk, right now is just annoyance those dinos might indeed subside in time but I hope it helps to know any form of direct assault is certain to work vs parameter tuning which affects corals, who aren't misbehaving. its such a tricky thing for large tanks....UV, you could clean this and siphon out the mats with hard work (not taking the tank down, a normal siphon cleaning) and once the tank is fully cleaned (but not microscopically) you install the UV and it cleans up the circulating bits you can't see but will remass soon.

If nobody has abused amazons return policy, then the 1st purchase of a giant huge oversized and costly UV can be evaluated and returned if it doesn't wow, but Id never return it. Id take it offline and keep for future serious battles, its your best hope for non anchored invaders in a large tank and if dinos get in, its your best initial chance of saving that big reef.
B

 

[Renan Isse]

UV doesn't seem to be trending here in Brazil, since the vast majority of reefs do not use it. Its price is similar to a good skimmer, so I'd rather invest in improving mine.

As far as I know, the UV filter will basically kill great part of my bacteria, which may make the stabilization process take longer, assuming my tank has not stabilized yet.

 

[brandon429]

no that doesn't occur at all, but I understand the cost. keep experimenting with grazers for sure as second best option.

one of the ways you can verify its harmless is by seeing what nano reef tanks do, thousands of them do 100% water changes which really does remove everything in the water, with higher coral density per gallon (which makes the case its not harmful to corals, we have 100% high end sps nanos doing 100% water changes) in some cases for more than a decade. Full water changes are always harsher than UV, but both are just options among many to consider, a large tank always has this type of engineering challenge at play so they can attack the invader and not harm the corals, very tricky for sure. neither technique is harmful, in fact employing the techniques is how we get uninvaded nano reefs that are over ten years old.

buying some of the competing organisms online you can get to make a sandbed more diverse might help, but that shipping might cost tons too depending on location.

 

[Randy Holmes-Farley]

Sorry, I forgot the pictures. Here they are. I believe it's not silicates, because they read 0.03 according to my salifert test, in my RODI water. Also, since I'm running GFO, it should also reduce the silicates in the tank.

FWIW, if they are diatoms, they need to, and are, taking silicate from the water. The 0.03 ppm is in the tank too, or just the RO/DI?

 

[Renan Isse]

FWIW, if they are diatoms, they need to, and are, taking silicate from the water. The 0.03 ppm is in the tank too, or just the RO/DI?

Last time I checked, it also was 0.03 ppm in the tank too. The point is, if they really are diatoms, they should be starving by now, or have already starved, since the silicate is low in the tank. I had once a silicate bloom that I dealt with by doing 30% WC with natural water for two or three weeks. Three months later, the tank become to be like this.

 

[Renan Isse]

no that doesn't occur at all, but I understand the cost. keep experimenting with grazers for sure as second best option.

one of the ways you can verify its harmless is by seeing what nano reef tanks do, thousands of them do 100% water changes which really does remove everything in the water, with higher coral density per gallon (which makes the case its not harmful to corals, we have 100% high end sps nanos doing 100% water changes) in some cases for more than a decade. Full water changes are always harsher than UV, but both are just options among many to consider, a large tank always has this type of engineering challenge at play so they can attack the invader and not harm the corals, very tricky for sure. neither technique is harmful, in fact employing the techniques is how we get uninvaded nano reefs that are over ten years old.

buying some of the competing organisms online you can get to make a sandbed more diverse might help, but that shipping might cost tons too depending on location.

Not only is shipping any kind of product to Brazil expensive, it also takes a loooooong time to get here if it gets. I've considered running an ATS, or seeding my sandbed with different kinds of bacteria, but I'm not sure if the latter would work.