Finding the root of my Cyano issue

[bat21]

Been having some decently heavy cyano growth lately. And I may have figured out the cause, but I want to see if you guys think this could actually be the culprit.

It's definitely not a nitrate/phosphate problem. They are both basically undetectable. But it occurred to me that I bought a new circulating pump about 2 months ago. The previous one was 600 gph and the new one is 568 gph. I didn't think 32 gph less would be a problem, but maybe it is?

Could the fact that I am using a SLIGHTLY weaker pump be just enough difference for cyano to be able to take root as opposed to before when it could not?

[outy]

Originally Posted by bat21

Been having some decently heavy cyano growth lately. And I may have figured out the cause, but I want to see if you guys think this could actually be the culprit.

It's definitely not a nitrate/phosphate problem. They are both basically undetectable. But it occurred to me that I bought a new circulating pump about 2 months ago. The previous one was 600 gph and the new one is 568 gph. I didn't think 32 gph less would be a problem, but maybe it is?

Could the fact that I am using a SLIGHTLY weaker pump be just enough difference for cyano to be able to take root as opposed to before when it could not?

Flow can be slightly attributed to it.


Usually though it is N and P.


Use a touch of chemi clean, and zap it, and see how you fair afterwards

[billdogg]

IMO, Cyanobacteria is as much a product of flow and lighting as it is anything else. Any excess NO3 or PO4 just make it that much worse.

[bat21]

There were no other changes to the tank in the last several months. No new livestock, lighting changes, differences in N/P readings. The only change was the new pump. It just seems crazy to me that such a small difference in flow can make such a big difference in cyano. But I guess there has to be a threshold and maybe it falls in between to two gph.

I have some little powerheads I'm not using. Maybe I'll put them in the DT to increase flow as an experiment and if I see a difference, maybe I'll just buy a stronger pump.

[CStrickland]

Yeah, and diff pumps have diff trajectories of water. Like a straight stream is diff than an all over turbulence, so it's not just a numbers game (plus I think they get creative with the numbers too). I like a few smaller ones so you can target problem areas.

[stingeragent]

How long has this tank been setup? While I will agree that the pump itself can make a difference as CS mentioned the flow pattern, I wouldn't attribute an outbreak to downsizing a pump by 32 gph. However if you replaced a wavemaker style pump with an old school style powerhead with a 1/2" output that could be the problem. Otherwise I'd say your outbreak was unavoidable.
Edit: Additionally, never discount nitrate/po4 as not being an issue even if your test kit reads 0. If something uses it up as it's made available your test kit will still say 0. Unless you have a way to check those levels 100 times a day, it's never truly 0. If you stick a chicken tender in your dogs bowl at 2pm, and then at 3pm use a "chicken tender tester" to check the bowl for chicken tenders, you a very likely to not get a chicken tender result from the test. Does that mean there was never a chicken tender in the bowl?

[Dkuhlmann]

stingeragent did your dog eat your supper?

IMO Cyano is all part of the cycle of a new tank and it will be there for several weeks. I tried everything that was suggested without any luck. So what did was collect the red mat with a plastic fork from my tank once a week, my cyano was limited to the sandbed so this was not to bad. After collecting all of the mat I did a 20% wc. It took about a month but one day after I collected the mat I noticed that none started growing after I cleaned it and never had it again.

[bat21]

Ok, the tank has been up for almost a year now. It's a Red Sea Max 250, 66gal AIO. My first tank. I also started with dry rock, so it was a fairly slow cycle. For the first 9-10 months, I had zero algae issues. And in the entire time it's been up, I have never measured any noticeable nitrates or phosphates. I've tried several different test kits since I wondered why I wasn't getting higher nitrate readings. On the Salifert low range test (the only one that can show me anything), it gets to about 2-3ppm. And that's it. I've tested pretty often too, since I'm always wondering why I never get nitrates.

I haven't added any livestock besides one fire shrimp in the last 4-5 months. The only change was the new pump. Before the cyano, and now with the cyano, I still read under 5 nitrates. Another thing is that I blacked out the tank for about 3 days at one point. The cyano was pretty much wiped out. I tested nitrates again, and no change. But then the cyano came right back in a few days.

So, this is why I am leaning towards the flow being the culprit. But I'm certainly not sure, and I am definitely still quite new to this hobby, and am also still extremely curious why my tank never accumulates any nitrates. It seems to defy logic, based on all of the experiences I read about on here.

But I have a happy little community of 8 fish, 3 shrimp, hermits, snails. I've never lost a fish besides a few that didn't survive their first 2 weeks after arrival (which happens to everyone). So I think I'm doing pretty well and am loving the hobby. Just trying to figure out exactly what's going on in my tank.

[Ron Reefman]

I think the flow issue is likely a big part of why you have an outbreak now and not before.

You may have been just at the edge of having a cyano issue, but you had just enough flow to keep it at bay. The change in flow was just enough to trigger the start.

My opinion is that cyano is a bacteria problem and nitrate and phosphate are not as big a factor in cyano as they are with problem algae. But what does cyano feed on... I'm not sure as I've never had an issue with it that wasn't cured with a touch more flow!

[CStrickland]

Cyano is bacterial. It needs carbon, phosphorus, and nitrogen but so does everything that is alive. The trick with cyano is the same as everything in our tanks: how does it get them? Like our fish eat phos that is bound to food, and pee out the extra as free phos that algae like to eat; and the bacteria that filters the water eat nitrogen as ammonia and poop it as nitrates, etc.

I don't think anybody knows for sure what cyano does, or if it does more than one thing. But if we prevent it from accessing one of its crucial nutrients, it will die. Once it does it needs to be removed so that it doesn't break down and feed the next batch, wet skimming seems to help that. Of the things I've read the ideas that make the most sense about nutrients are:

• For carbon, cyano uses light to get carbon dioxide from the water. Three days lights out interrupts this process I think.
• For nitrogen, cyano can use a few diff forms, so it doesn't need a high nitrate sitch but can compete with our "good" bacteria for ammonia (some algae do this to a certain extent as well, but will suck up nitrates too, whatever's easier). It can also catch nitrogen from the nitrogen gas that is the last step of denitrification, so when nitrates are converted out of the water cyano is grabbing them before they float away.
• For phosphate, cyano is very well adapted to new tanks. Perhaps using either free or bound phos, or just really good at competing for free phos

I think the phos is why it likes low flow. Say you are running gfo, or something else to remove the free phos from the water after the poop and food decay. You will have zero phos in the water that reaches the reactor, but the phos bound in poop/leftover food will accumulate where those land (dead spots in your flow, down in between the grains of sand at the surface of the sand bed) and the cyano grows on top, which also keeps them from blowing away. There it can eat the phos either directly or as it is released as free phos into the water, before it is carried to the reactor/scrubber/skimmer.

Just my thoughts, I'm not a chemist or anything.

[bat21]

Well, as I was installing my extra powerhead for more flow, I snapped the stupid plastic arm that attaches to the suction cup. So that's now garbage. I guess I'll just have to buy the stronger pump. Once I get it, I'll do another 3-4 day blackout period, and then hope the Cyano doesn't come back. It's a fowlr, so I can do as many blackouts as I need. I'll measure N/P twice a day to see if I can notice any changes, though I doubt I will.

[Dkuhlmann]

I had that happen to me and I used super glue and "fixed" it. Yes it actually worked

[bat21]

So I looked into it a little closer and realized that red sea, in the manual, for some reason, rounded 2400 lph to 600 gph, when it's in fact 634 gph. I bought a 568 gph pump thinking that was close enough. So it's not just a 32gph difference, its 66. Still not crazy, but now its more than 10% less flow. So I got the next one up which is 714 gph. We'll see how things go over the next couple weeks. But the flow seems even more likely to be the culprit here. Might even use the 568 to replace the recirculating pump which is only 300. Cyano won't stand a chance!

[CStrickland]

Wait, is your return pump the only current in the tank?
Cause 600 gph in a 66 gal tank is not much
I have 2,000 from powerheads plus 350 from the return on my 55 and I still have dead spots. I think something around 40x the display volume is pretty standard?

[bat21]

Originally Posted by CStrickland

Wait, is your return pump the only current in the tank?
Cause 600 gph in a 66 gal tank is not much
I have 2,000 from powerheads plus 350 from the return on my 55 and I still have dead spots. I think something around 40x the display volume is pretty standard?

600 (now 714) return pump and a 300 recirculating pump. That's what the tank comes with. People do sometimes add powerheads to supplement the flow, but I'm only using it as a fowlr, and only recently did this cyano issue crop up. So it was definitely enough flow before and situated in a way where I did not have any dead spots.

That said, I am probably going to bump it up even more now that I've seen the effects of not enough flow first hand.

[bat21]

Figured I would post a follow up here. I solved the mystery of the cyano arrival. It wasn't flow. It wasn't excess nutrients. It was simply aging t5 bulbs. I started with 3 actinic and 3 10,000K white bulbs. They were only about 6-7 months old when the algae started, and it just got worse and worse. I decided to remove 2 of the 3 white bulbs as a test, and the change was staggering. All the research I did, the evidence for old bulbs causing algae was very sporadic. But I am here to say unequivocally, they do. I have since replaced those white bulbs with new ones and there is no more algae. I can leave the lights on for so much longer now without there being a brown carpet of algae on the sand by the end of the day. So let that be a lesson to you. Replace your whiter bulbs. As they age, they tend to shift more towards the red spectrum, which algae loves.

[CStrickland]

Thank you for coming back, very considerate. And glad you sorted the cyano!