The dreaded dinos???

[Reefer1978]

I don't see any flagalates coming off the spherical 'things'? I would say it looks more like phytoplankton with cyano.

@twilliard get your head out of the books for a moment and help us!

Very possible... but usually I see phyto cells more perfect circles... and I much doubt Thor2j pulled 4 phyto cells within a single small sample. I dose phyto into my tank daily and I've never caught a single particle under the scope.

 

[Thor2j]

There defiently were not any "tails" coming off the spheres. Intertwined.

 

[Thor2j]

I need to vacuum that stuff out. Should I do it through a water change or siphon it through 2 filter socks and put the water back??

 

[mcarroll]

I would siphon out all the algae you can as well as the top 1/2" of sand. I would do it as part of a water change so you don't have to put the water back in.

 

[reeferfoxx]

I would siphon out all the algae you can as well as the top 1/2" of sand. I would do it as part of a water change so you don't have to put the water back in.

What's the plan if it grows back?

 

[mcarroll]

Wait and see first....it may not.

If it does, I'd peel the sand bed back 1/2" by 1/2", water change by water change until either the sand or the cyano is permanently gone. I might even advance that plan toward full-removal and suck 1/4 of the sand out now. Get it 1/4 at a time over the next four water changes. Space em out at least a week just for comfort.

It would all depend how the tank and numbers looked over the next week though...

 

[Thor2j]

I vacuumed all the algae out before my blackout. It still cane back. Guess I'll vacuum more out with a water change

 

[Thor2j]

What's the plan if it grows back?

It did

 

[mcarroll]

Yeah, sand removal I think has to be at least part of the plan. The question to me is whether you just want to go ahead and remove it all....balance the tank with a big water change and start over with new sand (or not)....or if you want to try a more incremental approach and just take out the top layer in hopes that the sand below is more-free of phosphates and won't serve as a cyano bed.

Nobody has said #diatomfilter yet. (Where's @Paul B?) Wouldn't running one of those during this phase help a lot? Marinland has a modern revision that uses their pleated paper micron cartdiges from the old Magnum filters, but it's formatted as an internally mounted powerhead/filter. For $40 it could be worth it. If I'm still not past my situation with my tank come tax season, I'll be getting one.

Mangnum Polishing Filter ($40-$50)

 

[mcarroll]

("remove it all" is still a graduated plan, btw......I wouldn't remove more than 1/4 per water change.)

 

[Thor2j]

Removed all algae in sand and some of the sand. Maybe 1/10th. Did this along with a 15% water change.

GFO has been out for 24hrs. PO4 on Hanna ULR registered 2

 

[reeferfoxx]

GFO has been out for 24hrs. PO4 on Hanna ULR registered 2

Can you clarify it was 2.00ppm or 0.20ppm or 0.02ppm?

 

[Thor2j]

Can you clarify it was 2.00ppm or 0.20ppm or 0.02ppm?

Thats phosphorus 2ppb which equals about 0.01 ppm. Hanna ULR

 

[reeferfoxx]

Thats phosphorus 2ppb which equals about .01 ppm. Hanna ULR

You did say ULR and I thought LR for some reason. They say nothing happens fast? I would at least wait another day and test po4 again?

Make sure you are monitoring alk and nitrates. Keep nitrates where they were. Prepare for more manual removal and water change, when the cyano looks manageable.

I know people suggest halting any carbon dosing? But after reading how the Redfield ratio works, I believe GFO isn't efficiently removing PO4 from the sand bed. Maybe more so in the rocks and less so in the sand?
To accurately remove the nutrients from the sand bed would be to reduce nutrients to zero via redfield ratio. 106ppm(carbon):16ppm(N):1ppm(P) . Doing this will increase bacterial production in and out of the sand bed. This would feed cyano and cause it to grow more. However, beneficial bacteria will populate faster and out compete nutrients. Keeping elevated nitrates to draw PO4 out is essential.

I might hate myself for this theory but I think its worth a shot. At least, that is my project.

 

[mcarroll]

Maybe more so in the rocks and less so in the sand?

It's a difference of surface area, IMO.

 

[mcarroll]

You're not off target, but the redfield numbers don't really work quite like that. Organisms on average tend to accumulate nutrients in that ratio while building their cells.

Nutrient levels are never constant in real life, and the variations are what dictates actual organism uptake....not redfield.

It's still instructive, because it does give perhaps an idea as to a problem, or how nutrient limitation works.

 

[reeferfoxx]

It's a difference of surface area, IMO.

I can respect that.

Can you explain this a little more?

You're not off target, but the redfield numbers don't really work quite like that. Organisms on average tend to accumulate nutrients in that ratio while building their cells.

Nutrient levels are never constant in real life, and the variations are what dictates actual organism uptake....not redfield.

It's still instructive, because it does give perhaps an idea as to a problem, or how nutrient limitation works.

Well, after seeing Thor's cyano images with the plankton, it had me thinking more. When I had read the redfield ratio, specifically wikipedia, they discussed the ratio but with plankton? They stated..

"Redfield discovered the remarkable congruence between the chemistry of the deep ocean and the chemistry of living things such as phytoplankton in the surface ocean. Both have N : P ratios of about 16:1 in terms of atoms. When nutrients are not limiting, the molarelemental ratio C:N : P in most phytoplankton is 106:16:1. Redfield thought it wasn't purely coincidental that the vast oceans would have a chemistry perfectly suited to the requirements of living organisms.

In the ocean a large portion of the biomass is found to be nitrogen-rich plankton. Many of these plankton are consumed by other plankton biomass which have similar chemical compositions. This results in a similar nitrogen to phosphorus ratio, on average, for all the plankton throughout the world’s ocean, empirically found to be averaging approximately 16:1. When these organisms sink into the ocean interior, their energy-rich bodies are consumed by bacteria that, in aerobic conditions, oxidize the organic matter to form dissolved inorganic nutrients, mainly carbon dioxide, nitrate, and phosphate."

 

[reeferfoxx]

Basically, if performing the carbon dosing and upping nitrate dosing with wet(maybe) skimming and weekly removal/water changes, that would drive nutrients to zero and starve cyano?

 

[mcarroll]

PO4 literally needs CaCO3 surface area to bond to. Sand has more surface area than a similar volume of rock, so....

Check out what's labelled "Table 2.01" in this blog:
http://blog.brightagrotech.com/biological-surface-area-in-aquaponics/

It's a table that compares the surface area of some common substrates, including medium sand and 4" rocks.

According to that table:

• sand has about 270 square feet of surface area per cubic foot.
• rock has about 12 square feet of surface area per cubic foot.

 

[Thor2j]

I know it has nothing to do with carbon dosing but I am running a carbon reactor as well. Should I leave that going during all this?