Brown sparse diatoms on san bed only

[Scubajoe1]

OK fellow reefers. General question for ya. I have been seeing some brown diatoms on my sand bed for a while. Not terrible but not nice and white either.

I have three radion Pro lights and two T5 lights on my system. Par levels on the sand bed are about 100-150 depending on where I measure.

The tank is about 10 months old now.

Phosphates are at 0 ppb using the phosphorus hanna kit.
Nitrates are about 1.5 ppm
Ca 445
Mg 1300
Alk 9.0

Everything is really rock steady and my Spotted mandarin that was eating pods actually just started gobbling up my brine shrimp today...guess he finally learned that 1 brine shrimp = 10 pods.

So my question is why the diatoms? The only thing I can think of is I have only siphoned my sand once but I do stir it now and then to get the detritus into the column and hopefully trapped by the filter sock.

Could it be I just need to siphon like once a week to clean the sand?

Thanks

Joe

[CStrickland]

is your rodi at 0 tds?

[Scubajoe1]

Originally Posted by CStrickland

is your rodi at 0 tds?

Water is 102ppm going into the system, 1 ppm after the membrane and 0 ppm and 0ppm after the first and second ion exchange filters.

[Isaacs55]

It's most likely your sand. If you stir up the sand bed your releasing the silicates that is left deeper in the sand bed that hasn't had a chance to deplete yet due to the silicate being buried. So I'm positive it's your sand for sure. The more you mess with it the more diatoms will keep coming back. My diatoms went away after I stopped messing with my sand bed and as soon as I stirred it up and messed with it my diatoms came back.

Siphoning it won't help in my opinion. Just leave the sand bed alone and let it do its thing. This is why most people rinse their sand a ton before adding it to the tank but they will still get diatoms because silicates will still be released.

[Dkuhlmann]

Originally Posted by Isaacs55

It's most likely your sand. If you stir up the sand bed your releasing the silicates that is left deeper in the sand bed that hasn't had a chance to deplete yet due to the silicate being buried. So I'm positive it's your sand for sure. The more you mess with it the more diatoms will keep coming back. My diatoms went away after I stopped messing with my sand bed and as soon as I stirred it up and messed with it my diatoms came back.

Siphoning it won't help in my opinion. Just leave the sand bed alone and let it do its thing. This is why most people rinse their sand a ton before adding it to the tank but they will still get diatoms because silicates will still be released.

This x2

[rovster]

If you figure it out let us know lol. I'm in s similar situation but mine is with cyano not diatoms. After a year I still get patches. When I vacuum the sand it stays clean for a week or 2 then slowly comes back. Have you tried adding a bunch of zombie snails, or a diamond goby? The sand in front of my pistol shrimp and goby hideout is always pristine lol!

[Scubajoe1]

I have a diamond goby, a tonga conch and lots of snails but not zombie snails. I have gone a month at least without touching the sand and there was no change. Just checked again today. Phosphorus 0 ppb and nitrates 1.5 ppm. I will try sucking the detritus out of the sand and see what happens. Will report back.

Joe

[Scubajoe1]

My Par is kinda bright at the sand bed about 150+ and in the darker areas there is no diatoms so not sure if I am getting too much light on the sand bed, Is this possible?

[Nano sapiens]

Quite common, actually. Age of the tank isn't a factor (I've seen posts from tanks in operation from 6 months to 7+ years with this issue).

What type of salt and how often do you do a water change?

[jpolack]

jeez

[Scubajoe1]

Originally Posted by Nano sapiens

Quite common, actually. Age of the tank isn't a factor (I've seen posts from tanks in operation from 6 months to 7+ years with this issue).

What type of salt and how often do you do a water change?

Red Sea Coral Pro Salt.

5% water change weekly. Clean skimmer weekly and change filter sock weekly.

[Scubajoe1]

Originally Posted by jpolack

jeez

Jeez?

[CStrickland]

Originally Posted by Scubajoe1

Jeez?

I wouldn't stress it. There's a bot check thing where new members have to make a certain # of posts to do diff things like add pics or sell in the trading subforum. So when you see a rando dropping concise nonsense in 10 threads in 5 minutes it's usually cause they are trying to play the spam filters.

For your prob, idk, I think you can dim the lights or change their spectrum to try to slow it down, and not disturb the sand; or you can crank up the lights and vac them out as fast as they come until they run their course, like ripping off a bandaid.
Might help to change your sock every other day. That'll get the dead ones out of the water column so they aren't just decaying and releasing the building blocks (like silica) back into the water for the next generation to use.

[Scubajoe1]

Originally Posted by CStrickland

I wouldn't stress it. There's a bot check thing where new members have to make a certain # of posts to do diff things like add pics or sell in the trading subforum. So when you see a rando dropping concise nonsense in 10 threads in 5 minutes it's usually cause they are trying to play the spam filters.

For your prob, idk, I think you can dim the lights or change their spectrum to try to slow it down, and not disturb the sand; or you can crank up the lights and vac them out as fast as they come until they run their course, like ripping off a bandaid.
Might help to change your sock every other day. That'll get the dead ones out of the water column so they aren't just decaying and releasing the building blocks (like silica) back into the water for the next generation to use.

Thanks. Well I found a great gravel sucker tonight. Check out my last post in equipment. I am also going to add the TIR 120 degree lenses I bought a while ago for my radions to reduce the hot spots.

[Nano sapiens]

Originally Posted by Scubajoe1

Red Sea Coral Pro Salt.

5% water change weekly. Clean skimmer weekly and change filter sock weekly.

Many times the salt used is one that is 'enhanced' far above normal sea water levels for major and minor trace element levels (some of them with added organics/vitamins, too). The thinking goes that too much of something (silicate for diatoms, etc.) is continuously fueling the sand bed bloom. Frequent water changes just keep supplying whatever these organisms need.

You could try a more natural parameter salt that is without added additional elements (tropic marin, red sea blue bucket, etc.). Decreasing the frequency of water changes has also been reported to work for some.

I've had this coondition in my 7 year old nano tank for about 10 months now. I can control it a bit by reducing nutrient input/vacuuming the substrate regularly, but it will not go away. I'm finally down to the last water changes with Reef Crystals and will start using an Instant Ocean/Red Sea Blue Bucket mix (70/30%) next week and monitor from there (10% WC/wk). If it doesn't clear up in a few months, I'll try a reduction in the frequency of WCs.

[CStrickland]

@nano - how much sand do you have?
I see a lot of these threads, never in a bb tank. So I wonder if more rinsing would help etc. Would help to know if the folks who have ongoing issues also have deeper beds or like an rdsb in a bucket.

Also, forgot to mention that phosguard absorbs silica, if you run a reactor. I feel like regular gfo does too. Might help push things along.

[Nano sapiens]

About 1". I started to see this issue when I switched to RC (contains added orgnaics), but can't say for sure if the salt was the deciding factor. The sand bed is vacuumed at least once a week, so it has less detritus than is typical.

This type of organism especially likes the sand bed as it is likely using the phosphate liberated by bacteria from the calcareous substrate. If these are indeed diatoms, then limiting silicates should be helpful in control.

In my tank, these organisms have not harmed the tank or other inhaibtants in any way and are just unsightly. Their appearance is driven by how much light is available (more light, more organisms). A quick 2 minute stirring of the sand bed and they 'disappear' to then reappear the next day.

Another factor to consider is the impurities present in additives. About a year ago I started using Ms Wages Pickling Lime exclusively since I had run out of my pharmaceutical grade kalk from Two Little Fishies. I'll be going back to the more pure product in the near future.