Diatom Help

[stcreef]

Since the end of August I have been fighting diatoms on the sand bed. Brown/orange (rust colored) dusting. It pretty much dies off over night then starts up again the next photo period.

125gal RR Long
60 Gal sump 3 sections(1st twin over flows into socks/skimmer (SumpBuddy 40)/2nd return/ 3rd fuge fed from return bypass)

Flowing about 1000 gph through sump plus 2ea. Koralia 4's and 2ea. Koralia 3's (used to have a CL with a DART and top mounted manifold with ten 3/4 in. LOCs) Switched it for the power heads thinking it might have been flow. That was a wasted effort

Mixed softy/LPS/SPS

4 chromis, 2 percs, 1 blue throat, 1 powder blue, 1 blenny, 1 firefish, 1 sixline, 1 exquisite wrasse

Plenty of cleanup crew, snails, hermits, stars

Kalk Reactor dripping for top off w/floats (Mrs. Wages)
Dosing 2 part (pedlow/baked baking soda)
Sulfur Denitrator (Dual Chamber Octo Cal Reactor)
ETSS Sumpbuddy 40 fed from outside charcoal filtered air
2 TLF reactors in series (seachem carbon and seachem phosguard)
Using Seachem Reef Salt
3 175w MH 14k & 4 96 watt PC's dual atinic (All less than 30 Days old)
PC's 10am - 8pm, MH 11am - 6PM

2 inch caribsea arag-live sandbed
180lbs live rock (was bleached/ washed and cooked for months prior to setup)

Tank up and running about 9 months


SG 1.026 (refract cal w/pinpoint 53ms solution)
PH ~8.1 (pinpoint & ACjr)
Temp ~80.5 F (ACjr and bulb type)

ammonia 0 Elos/Sera
nitrite 0 Elos/Sera
nitrate 0 Elos/Sera
PO4 0 Elos/Sera
Silica 0 Salifert/RedSea
cal 480 Elos/Sera/Seachem
alk 10dkh Elos/Sera/Seachem
mag 1350 Elos/Seachem

I thought maybe it was my RO/DI (5 stage fed with well water) switched to a dual DI with silicamax carts. 0 TDS with calibrated handheld. Plus tested for silica/phosphate and nitrate. No go.

Removed the socks thinking maybe it was silica from the washer since its well water. No go.

Stopped all kalk dripping since under certain conditions it can precip silica. No go.

Switch all bulbs to new. No go.

Tested salt mix for silica/phosphates/nitrate...No go

I usually do 25gal changes every 2 weeks/ but stopped to see if it changes. No go

I vacuum, its back the next day.

I run a diatom filter, its back the next day.

Everything in the tank is healthy and growing. Feed Spectrum pellets 1-2 times a day and Rod's Food twice a week. I even tried cutting back for a few weeks. No Go.

Soaked food in tested RO/DI then tested for silica/phosphate/nitrate. No go.

But yet the glass I only have to lightly clean every other day.

I am sure I have forgotten something here. About the only thing I havent tried is a complete lights out. But I am sure it would come back because obviously there is silica getting in someplace.

I have tried 3 different skimmers. Still not happy with the way this one skims.

I am pulling my hair out and there isn't much of that left. Uggggggg

 

[Hawkeye]

one of the most thorough posts I've seen...

only thing i can think of is maybe the sand was a bad batch and has silica in it.

You mention your cleanup crew...can you be more specific? What kind of cleaners do you have for the sand?

 

[panmanmatt]

Diatoms are a normal part of a newer tank and yes 9 months is still new. The best thing to do is leave them be and let them run their course. The more you mess with them the longer it will take for them to go away. Yes it is unsightly but they should go away in 2-3 weeks if you let them.

 

[mott768]

Cerith and Nassarius snails, plus cucumbers are all good and help with the Diatoms, but like Matt said you should let it run it's course.

 

[stcreef]

phil, figured I would put in as much as I could rather then fill up the thread with "tried it, did it"'s

As far as cleanup.....

Nassarius
Cerith
Astreas
Turbos
Scarlet Hermits
Blue Hermits
Zebra Hermits (Mean little devils)
Emeralds

No cuc's but was thinking about it, any certain types?

I checked the sand here and there and haven't found any hint of silica.

I had switched to the dual DI because I was detecting a hint of silica prior too, but its been a month since I switched.

 

[Hawkeye]

I dunno - diatoms should come (with a vengeance) and then go...to me the fact that they keep reappearing week after week is just strange.

Astreas are awesome for the glass (and somewhat for the LR) in terms of diatom eating. Do you think the glass has less because it is being cleaned up more effectively or do you think there isn't a lot appearing on the glass period?

In terms of the sandbed crew - how many nassarius/cerith? it's a 6 foot tank so I figure you have quite a few...just making sure.

oh and the cukes that would be ideal would be the ones sold from the carribean. They are fairly ugly but do the job. The colorful ones from the pacific are typically filter feeders and a bit noxious.

btw- i liked the details on the post - that's what I meant by thorough. If only everyone could do that!

 

[panmanmatt]

They keep coming because they are being disturbed. They are feeding off of the silicates, once they are totally gone the diatoms will go away. He was adding silicates with his water thus he changed the filters. The reason they are not showing up on the test is because they are bound up in the diatoms.

It is the same reason that folks with hair algae can't read nitrates the algae is binding them as fast as they are produced.

 

[stcreef]

I can clean them up and they will be back the next day. You can see them almost grow once the lights come on.

I think the glass is staying clean because of the flow in the tank. There seems to be some discrepancies but I have read that the brown/orange/gold on the sand is actually the skeletal remains of the diatoms and not actually alive. But I have only seen that referenced in other forums not in any texts. So not sure how true it is.

Yes there is quite a few snails in the tank. I would think almost too many. You can definitely see where the snails make a dent.

The only other place I can think the silica would be coming in is either one of the rocks or the Pedlow I am using for the two part. Its a bucket that is a few years old. I may just order some from BRS. Its been going on too long now. Since August and really hasn't receded. So all my efforts is keeping it at bay for now. I could see a few weeks but this is going on 2 months.

Its getting to the point that I am starting to believe that it isn't diatoms but something else. Any one know of someplace local I could take a sample to be identified? Maybe the NJ Aquarium?

 

[Hawkeye]

we're not the nj aquarium - but curiosity is getting the best of me - how about posting a few pics?

 

[stcreef]

Lights out....I'll get a pic tomorrow and post. See...I knew there was something I was forgetting. Its been a long two months and frustration has set in.

Was wondering if anyone knows any biologists or someone down at the aquarium that may take a look at a sample for me. I may just call down there and query for some help. I know there are some dino's that can be mistaken for diatoms.

 

[panmanmatt]

Well for the first month or so you said your RO water was testing positive for silicates so in essence you were feeding them. It is very possible that you put enough of it in there to keep them fed this while time. Plus you have to also remember that as you are removing them either by siphoning them out or with what the snails are eating is leaving more silicates for the others to feed off of thus they will keep reproducing. That is why it is best to just let them be and they will starve themselves out.

The more they are disturbed the longer they will be around. This is one of those cases where the less you do the better off you are.

 

[stcreef]

panmanmatt, I understand what you are saying but with that logic I am not quite understanding what would be the export method, other than the skimming. But that wouldn't take care of what is laying on the sand. So in that instance there would always be a high level of silicates bound up on the sandbed. So they would always need to be disturbed in order for the skimmer to export. Which reminds me. I have also added a third TLF with some SERA Silica filtering media. So that is a second export method that is deployed.

 

[panmanmatt]

The diatoms are eating the silicates, that is the export method. Just like folks using chaeto in a refugium to export nitrates. Silicates are all that the diatom algae feeds on, once they consume it they starve out. As long as you are not adding any silicates they won't come back as they have no food source. As the diatoms die off they are removed through skimming and other filtration.

 

[stcreef]

ok this is going to sound silly ....

I took a small piece of rock and placed it in an area where I get the heaviest of this bloom. Waited a few days for it to get a dusting on it. I then drove down to the local Toys-R-Us and bought a cheap 1200x microscope (thanks to my 10 year old for the idea). Pulled the rock, scraped the dusting into some RO water, shake not stirred and put it on a slide.

After looking at slides online of diatoms and dino's I can say with confidence that it is diatoms that I have.

The optics of the microscope are crap. But I will say that its interesting to see all of the life at that level. I highly recommend for those interested to get yourselves a microscope. Even if it is a cheap one. Even at 300x you can see plenty of life.

 

[Hawkeye]

is it possible to take a picture of the contents on a microscope? not with normal cameras right? ???

 

[stcreef]

They do make usb cameras that can be fitted to standard microscopes......you can look at Edmund Scientific. But they get rather expensive just for the occasional use.

 

[Hawkeye]

figures....

so back to the thread - you have diatoms. Maybe this time let them run their course? What do you think?

 

[stcreef]

yeah....looks like it.....I am going to take some samples of RO/DI water and tank water over to my buddies at Rohm&Haas to test just to make sure I'm not still getting silicas. The hobby test kits I'm not too comfortable with the results. Even after adding the Silicabuster DI carts, my test kits still show a hint of color. So whether that means there is or isnt still silicas, who knows. Stay tuned.....

 

[stcreef]

Ok figured I would update.

RO/DI tested negative for any silica. So that made me happy. My tank water showed no signs either but obviously its there or there would be no diatoms. We took some samples of sand and added some water and let them mix for a few days, then tested the water for silica. Also negative. Then I took the filters off of my hood fans and let them soak in water, then tested. BINGO, off the charts. So I have since tripled up on the foam filters on my fans and wash them once a week. Also since I suck air in from outside for my skimmer, I have added a rather large DIY GAC filter to the outside. The bottom sump area of my stand was open, I added a black curtain across the back. I have also added about 2 dozen 1 inch nassarius snails and a few more dozen ceriths.

Finally the diatoms are almost gone. There is only 2 spots left right now and they are receding. Its nice to see white sand again.

 

[Phyl]

Wow. Amazing that there is so much silica in the air. Thanks for the update.

Do you worry that closing off the sump area of your stand is going to cause an increase in CO2 buildup?