What causes the brown diatoms?

[d2mini]

The most obvious cause for me in my nano all of a sudden is the light. As soon as the lights come on in the morning, the sand is clean but the diatoms start. Within hours the sand is all brown. Then the lights go off at night and by the next morning the sand is clean and it starts all over. This is a brand new occurance for me that started a couple weeks ago. I'm also getting micro bubbles attaching themselves to my macro algae. Again, these go away at night.

But why would the light all of a sudden start creating issues? This leads me to believe there is an underlying cause that is exacerbated by the light. Any ideas?

The light is an led fixture.

 

[bjohanson1234]

The bubbles on the macro is probably oxygen from photosynthesis.

Is this a new tank? Diatoms darken during the day like that. They are photosynthetis also. Once they use up any silicates in the tank, they will die off. Just keep up with your water changes and they should go away in a few weeks.

 

[d2mini]

No, old tank. It crashed at one point but it's been back for like 6 months.

 

[RockStacker]

Check this out.
Hopkins Marine Station - Diatoms
It could explain why the diatoms congregate on the solid surfaces when light is available.

It is also possible that at night the diatoms float in the water column and are skimmed out. Then during the light phase, any remaining diatoms sink back down and start reproducing again.
This cycle would continue indefinitely until they run out of silicates to build their shells.

 

[Bifferwine]

You sure it's diatoms? Dinoflagellates usually respond to light in that way, and air bubbles are characteristic of dinos.

 

[d2mini]

Yeah, i forget about dinos. Could definitely be that as it gets a little stringy by this time of the day.

 

[Bifferwine]

Now Dennis, I know you are an amateur with the camera, AT BEST. I mean, it's probably going to come out all blurry and dark and maybe with a dog walking in the way of it, but could you maybe post a picture of it? I'll try my best to ID it from your shoddy photography work... :mrgreen:

 

[chichimom79]

Now Dennis, I know you are an amateur with the camera, AT BEST. I mean, it's probably going to come out all blurry and dark and maybe with a dog walking in the way of it, but could you maybe post a picture of it? I'll try my best to ID it from your shoddy photography work... :mrgreen:

ROFL, I can't wait to see these awful pics.

 

[Bifferwine]

ROFL, I can't wait to see these awful pics.

I know it's a stretch, but I figured it was worth asking... ;)

 

[d2mini]

buncha comedians round here! :D

Here ya go.

 

[Bifferwine]

I'm pretty sure those are dinos. I see stringy bubbles in the second picture. :(

 

[d2mini]

Yeah.

So now what?
Like I said, they go away at night.

 

[Amba]

Water changes, low feeding, and careful manual removal and near zero phosphates will all help. Good luck, these things are a PITA.

 

[Ted]

Would a black out for a couple of days break the cycle? I would think it would be worth a try.

 

[d2mini]

Would a black out for a couple of days break the cycle? I would think it would be worth a try.

tried that already.
And i already nearly starve my fish.

 

[Amba]

Blackouts usually don't do much for dinos. Dennis what is your PO4 in the nano?

 

[bjohanson1234]

If you can, set up an algae scrubber. I had a dino outbreak and it went away when I set up the scrubber. I believe that it gave them a better place to live and since you clean it off weekly, they eventually died out.

 

[d2mini]

This is my 6g Fluval Edge at my office so I'm limited.

I went ahead and did another water changes this morning and did a long overdue cleaning of the filter tray. Changed out the carbon, cleaned the filter sponge, and changed out the ecobak ULNS pellets.

Maybe all that will help. Not much else I can do.

 

[Amba]

By carbon do you mean chemipure?

 

[d2mini]

no, just black carbon.
The little sachets that fluval sells specifically for the edge.