If I said I had cyanno everywhere, what would you tell me?

[Vette67]

A month or so ago, I noticed cyanno starting to pop up all over my tank. It seemed to prefer my 75 gallon tank, and my 40 gallon refugium glass. But I have also been noticing it on the rocks in my 180 DT. Tank has been set up since 2002. So a LONG time. Well established. Conventional wisdom would say elevated nutrients. My phos is .06 and nitrate is about 20 (somewhere between 15and 25 on the Nyos scale). Nitrates are slightly elevated, but by no means obnoxiously high. So I turn up my skimmer and start skimming wetter. This does nothing. In the meantime, I do an ICP test. Results say everything is normal, except potassium. Test says K is 316. Pretty low. So I start dosing K. Problem is, I can’t get it above 370 (Salifert kit). So I start dosing twice a day. Still waiting to see if I can get it to increase more. Well today, I notice 90% of the cyanno is gone, mostly replaced with a green turf algae. So I’m wondering if there is a relationship between cyanno growth and low potassium. Now I can’t say for sure that dosing K reduced my cyanno, but it sure seems too coincidental to be ignored. Like gone within days of dosing K. And that has me wondering if perhaps conventional wisdom is not so conventional.

 

[arking_mark]

A month or so ago, I noticed cyanno starting to pop up all over my tank. It seemed to prefer my 75 gallon tank, and my 40 gallon refugium glass. But I have also been noticing it on the rocks in my 180 DT. Tank has been set up since 2002. So a LONG time. Well established. Conventional wisdom would say elevated nutrients. My phos is .06 and nitrate is about 20 (somewhere between 15and 25 on the Nyos scale). Nitrates are slightly elevated, but by no means obnoxiously high. So I turn up my skimmer and start skimming wetter. This does nothing. In the meantime, I do an ICP test. Results say everything is normal, except potassium. Test says K is 316. Pretty low. So I start dosing K. Problem is, I can’t get it above 370 (Salifert kit). So I start dosing twice a day. Still waiting to see if I can get it to increase more. Well today, I notice 90% of the cyanno is gone, mostly replaced with a green turf algae. So I’m wondering if there is a relationship between cyanno growth and low potassium. Now I can’t say for sure that dosing K reduced my cyanno, but it sure seems too coincidental to be ignored. Like gone within days of dosing K. And that has me wondering if perhaps conventional wisdom is not so conventional.

Was there green turf algae b4 the cyano appeared?

 

[Jekyl]

When it first started showing up was it after a large water change or some other kind of change? Mine kicked in because of a long over due large water change. In about 3 or 4 weeks it was gone on its own.

 

[Vette67]

Hard to say. I can’t remember what I had for lunch yesterday, much less what my tank glass looked like a month ago. I’m going to say no, because I don’t remember any being there. Maybe a turf algae isn’t an accurate description, but it has turned more brownish green than the dark red color that it used to be. So it is being replaced by something but I can’t say exactly what for sure. You can see this pane was once fully cyanno, now just the bottom section is.

 

[Vette67]

When it first started showing up was it after a large water change or some other kind of change? Mine kicked in because of a long over due large water change. In about 3 or 4 weeks it was gone on its own.

For me a water change is about 35 gallons on about 350 gallons of water volume. So I wouldn’t call it a big water change. I do those about once a month and haven’t typically associated cyanno outbreaks with a water change. I will definitely pay more attention now

 

[Jekyl]

Not so much as just a water change. I've seen others say cyano was triggered by a parameter shift. Could be from elsewhere. Yours is more severe than mine was though.

 

[Vette67]

Not so much as just a water change. I've seen others say cyano was triggered by a parameter shift. Could be from elsewhere. Yours is more severe than mine was though.

That’s the thing is I can’t imagine what parameter shift that might be. Agreed, I have had cyanno come and go over the years, and I mostly pay no attention to it. It sometimes waxes and wanes on its own. But this time I noticed a more dramatic shift downward, after changing something (potassium dosing); which had me questioning whether or not there may be an association.

 

[arking_mark]

That’s the thing is I can’t imagine what parameter shift that might be. Agreed, I have had cyanno come and go over the years, and I mostly pay no attention to it. It sometimes waxes and wanes on its own. But this time I noticed a more dramatic shift downward, after changing something (potassium dosing); which had me questioning whether or not there may be an association.

How is your water flow? Pumps drastically lose performance over time if not cleaned regularly. I've noticed cyano in low flow areas at times.

 

[Vette67]

How is your water flow? Pumps drastically lose performance over time if not cleaned regularly. I've noticed cyano in low flow areas at times.

Well admittedly, my flow is purposely low in my refugium, to encourage pod growth, and not blow them around everywhere. And that picture is from my 40 fuge. But in my DT, that is not the case.

So it seems something changed, for sure, but I guess the consensus is that it has nothing to do with low K. I just thought I would throw that out there and see if it got any traction...

Again, I’m not too concerned about cyanno. It comes and goes without much fanfare and I never lose sleep when it appears. I was more noticing how quickly it seemed to diminish this time, and the only thing I changed was K. Perhaps it is just coincidence....

 

[arking_mark]

Well admittedly, my flow is purposely low in my refugium, to encourage pod growth, and not blow them around everywhere. And that picture is from my 40 fuge. But in my DT, that is not the case.

So it seems something changed, for sure, but I guess the consensus is that it has nothing to do with low K. I just thought I would throw that out there and see if it got any traction...

Again, I’m not too concerned about cyanno. It comes and goes without much fanfare and I never lose sleep when it appears. I was more noticing how quickly it seemed to diminish this time, and the only thing I changed was K. Perhaps it is just coincidence....

I'm not discounting the potassium. I'm not knowledgeable enough about cyanno....so you may be on to something.