Organics and dinoflagellates

[Cory]

So ive noticed a trend in my tank. Every time my sump gets full of detritus as the picture shows, long stringy dinos begin to grow in the display.

After i clean it out, the dinos disappear. Its become so predictable that im sure its a cause.

Anyone noticed this? Is there any science behind this?

 

[biom]

decaying detritus=nutrients+trace elements, nutrients+trace elements+light=dinos, so no detritus, no dinos

 

[mcarroll]

If it wasn't the dino's it would be something else though. Just happens they are the lucky critter in your system on the tipping point of a bloom.

I think it's a more general sign that the system's nitrogen cycle is fully loaded...the extra detritus between cleanings is all it takes to tip the balance. Once there's excess nitrogen (prolly other nutrients as well) in the system, something in the tank's microbial food web will sooner or later take advantage of it.

Result: bloom of something!

How has the tank's overall stability been over the last 6 months or so? And how old is it?

 

[Cory]

Stability is good I think. Po4 ranges from 0- .13ppm. No3 is always undetected. I have an algae turf scrubber. I dont use a skimmer because it broke months ago. Alkalinity previously was maintained at 8ish dkh. So pretty stable besides po4 being my only concern sometimes. Tank is about 8 months iirc.

 

[Randy Holmes-Farley]

The dinos (if that is what they are) might be there due to elevated inorganic nutrients, or organics, which some dinos can consume.

There are many different dinos with different means of getting energy. Some are photosynthetic and some not. Some prey on other organisms, and some do not. etc.

It is certainly true that photosynthetic dinos need N and P and probably get it from inorganic nutrients, and it is also known that some take up organics such as acetate.

FWIW, I have a thick mud in my sump since I have not cleaned it out for many years. But no dinos there. A few sponges and vermitid snails, but not much else I recognize.

 

[ksed]

interesting that it appears the scrubber is maintaining your No3 but not the Po4.

 

[Randy Holmes-Farley]

Obviously it may relate to the relative amounts of N and P in his foods relative to the turf algae, but it may be in part due to other means of nitrate reduction which do not exist for phosphate, such as denitrification in live rock or sand.

 

[Cory]

Ive got sand, and i think it contributes to no3 reduction at the expense of reduced po4 reduction of the ats.

Do organics degrade and release acetate Randy?

 

[Cory]

Oh what about my ro unit, its got 2ppm tds, is acetate coming through?

 

[ksed]

Obviously it may relate to the relative amounts of N and P in his foods relative to the turf algae, but it may be in part due to other means of nitrate reduction which do not exist for phosphate, such as denitrification in live rock or sand.

Totally over looked that.

 

[Randy Holmes-Farley]

Ive got sand, and i think it contributes to no3 reduction at the expense of reduced po4 reduction of the ats.

Do organics degrade and release acetate Randy?

Yes, acetate is a decomposition product of some organics being broken down. It too breaks down.

 

[Randy Holmes-Farley]

Oh what about my ro unit, its got 2ppm tds, is acetate coming through?

Very unlikely. All organics are pretty big relative to water (except methane) and so would be rejected by the RO membrane and are not in tap water are high concentrations to begin with.