Cyano rearing its head

so I am a bit puzzled at this, but I am getting a cyano outbreak in the tank. it grows in a few areas and I really want to get rid of it. I cannot nail down the cause of it either.

I am running ecobak since christmas, and run GFO for 12 hours every day. nitrates, nitrites and ammonia are all zero. Phosphate is .04ppm per Hanna checker. ph 8.18, KH is 7.5. salinity is 1.026. I use RO/Di at zero TDS for all new water additions.

was considering using a red slime remover, but dont want to deal with the massive water change as the system has about 250 gallons of water total and I dont have the salt for that. i have been a subscriber to the no water change club for about 8 years now and this issue never came up in my old tank. just this new one. the cyano is NOT on the sand, but on a few of the rocks.

 

Well, as you know cyano bacteria can give you false readings on your tests – have you manually removed the cyano and then tested the water over the next two days? Often times you will see the culprit and then you can hone in on the cause.

How about your skimmer ? is it producing ? I know you have posted these thread in the recent past so there is probably no need to go through the usual laundry list of items.

Any chance you have dead spots in the tank giving rise to C0’2 and feeding the bacteria?

 

I can't help ya with the "how it got there". But I had it pretty bad back during the holidays. It got worse will I was away for a week recovering from surgery (my GF helped with the :verfeeding lol). Anyways I used 1/2 cup of BRS high capacity GFO in a TLF reactor, and I changed it out every 7 days. It was completely gone in about 4 weeks. Hope this helps good luck.
EDIT thats 1/2 cup for about 60 total gallons

 

CG, yea running an MRC2 skimmer and pushing at least 1000gph thru it. that said, I may have it set too dry and need to wet it up a bit. dont have any deadspots in the tank with at least 60x turnover on it.

yea, I know phosphate can be very hard to test for. hence the Hanna meter so I can get the most accurate reading. I am thinking it is some residual leeching from the rocks due to some earlier issues I had. I really dont want to use a remover on it, so i am doing my best to suck it out with the baster, but when I blow it off to get sucked up, it floats off too quickly. Guess I should turn off the big pumps for a bit...

lastly, I did have a bad HA problem I solved with algaefix. that stuff was AWESOME and tha tank looks good but with some patches of maroon here and there.

 

A Hanna Checker is not nearly accurate enough to detect phosphate at levels that would limit cyano. It is only accurate to the reading +/- 0.04 + 4% of the reading. To limit cyano, you need to be significantly lower. The Hanna phosphourus ULR checker can get closer (reading +/- 0.015 + 4% of reading, although you will need to convert phosphorous reading to phosphate), but that still may not be enough even.

Also, the reading is somewhat irrelevant anyway as cyano can likely consume organic nutrients.. Could even be feeding of the HA dieng off, or the Algaefix itself (I'm not sure what's actually in it, if it has organic molecules for example). Therefore, it would not need to wait for decaying organic material to decompose into the inorganic forms which could be detected by a test kit.

Also, why run GFO 50% of the time? If you have cyano, you probably arn't running it enough. Phosphate levels in the ocean are around .005ppm. No matter how much you run GFO, you are unlikely to get down to that level in a closed system.

Anyways, my standard answer for cyano:

1) Run GFO change out often.
2) 15%ish per week water changes using RO/DI water.
3) Run lots of carbon and change out weekly.
4) Wet skim
6) don't overfeed
5) siphon out existing cyano, or increase flow to get cyano and detritus into water column to be skimmer out.
6) Good clean up crew to consume excess food.

 

M.. thanks, I was only running it partly as i ran into an issue with it a few months back where I stripped it down too far too fast and burned teh crap outa my corals. I am working it back to more often.

as for overfeed, I do not. I have three large tangs that get fed once daily. I do need to bump up the cleanup crew and increase my detritivores per some cleanup I did in the tank tonight. I siphoned a ton of it out.

 

well you mentioned it earlier today... but I would say that your source is leeching from your rocks/sand.
And to also enforce your other theory, when I have some gha that dies out it almost always gets covered in cyano as it is decaying.

I would put my money on these being your sources so homefully you should be seeing some improvements very soon

 

I hear ya about annoying corals. Ramping up the GFO too quick can definitely do that. What do you do when it is not running though? I'm not sure it's a good idea to leave it stagnant. Or are you doing something else? May be better to just run smaller amounts and build up slowly. Actually IME the reaction of my LPS corals to GFO is pretty quick. So, would probably still prefer to run a little and ramp it up slow.

As to overfeeding, the other thing to consider is rapid changes in food quantity. If you cut back too fast it can also lead to die-off and cyano. All the pods and critters, microalgae, bacteria etc.. need to eat. They all either directly or inderectly get their food from the fish food you feed. So, cutting back too quick or too much can cause die off which cyano will tend to feed cyano.

Based on what you've said, that dosn't sound like the case, but just something else to consider. In your case, based on the info so far, it sounds like the HA dieoff fed the cyano. HA can accumulate lots of nutrients, trace elements etc... When it dies off, it releases it all.

 

we have been HA free for about a month now. when It died I pulled it all out of the tank as best I could.

 

Oh yeah, I recall one of your older posts now – you had mentioned that you thought phosphates might be leeching from your rock. Are there any smaller rocks you might be able to pull out and put in a bucket for a while in order to test the water?

Do a small water change, take a couple gallons of old water to a bucket with a small heater and air stone – drop in the rock and test phosphates, test again after 8-12 hours and see what you got. At least then you would know for sure it’s the rock.

Kill the large pumps before you blast it off the rocks – alternatively get a bucket and a small hose (larger than an air line but not by much) and suck the cyano off via a siphon – this will resolve the current grabbing the blown off cyano before you can.

I can’t recall, do you have a refugium? Drop the cyano into the refugium and let it propagate there. I have plenty in my refugium (I put it there) – my DT is clean.