Cyano Problem – Zero Nitrate, Low Phosphate

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flight82

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Hi everyone,
I just wanted to thank you all for the contributions and insights — I really appreciate the support.

I’m sorry if my post led to any unproductive arguments. That was never my intention.

@CHSUB — I now understand what you meant: that nutrients might not be truly absent, but rather being absorbed by algae or other organisms, making them undetectable by test kits, which aren’t perfectly accurate. That makes sense. However, I have to say that this wasn’t clear in your first reply. The very direct tone made the message, in my opinion, feel confusing and somewhat misleading.

Just to add some context: the algae on the bottom glass started appearing about a week after I increased feeding for the fish.
I ran tests yesterday and got 0 nitrates and 0.11 phosphates — so apparently, the extra food is increasing phosphate levels and triggering algae growth, which I didn’t have before.

Thanks again to everyone for the constructive feedback!
 
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VintageReefer

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Hair algae growth in your tank is arguably irrelevant to phosphate numbers. I kept my phosphate from undetectable to .05 on Hanna for 2 years, then over the next year increased phosphate to 1.03, then back down to .30-.40 which is where I am stable today. Regardless if I was 0.0 or 1.0, I gave not had hair algae problems and my clean up crew is very small

Sure, phosphate plays a part in algae, but “elevated” phosphate levels does not always correlate to elevated algae issues
 
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Hair algae growth in your tank is arguably irrelevant to phosphate numbers. I kept my phosphate from undetectable to .05 on Hanna for 2 years, then over the next year increased phosphate to 1.03, then back down to .30-.40 which is where I am stable today. Regardless if I was 0.0 or 1.0, I gave not had hair algae problems and my clean up crew is very small

Sure, phosphate plays a part in algae, but “elevated” phosphate levels does not always correlate to elevated algae issues
Thanks for your input — I think maybe my English (I'm Italian) didn’t fully express what I meant.

Since I increased feeding to try and raise nitrate levels, I’ve seen a rise in phosphate and the appearance of algae on the bottom glass that I didn’t have before. I didn’t mean to say that the algae are caused by phosphates — just that these changes happened together in my case.

Thanks again for the discussion and for sharing your experience!
 

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I see fish and algae, so basically toss your hobby test kit results because they are worthless. If you want less nuisance algae start by removing it….it’s that simple! After that, maintenance and CUC will maintain a clean nuisance algae free aquarium until you fill it up with corals. Then you can, maybe, start worrying about nutrients but that is a long way off.
Pretty rude and sarcastic comment for someone seeking help.
I want to point out that you are wrong.
He should work on increasing nutrients first... then the algae/cyano will go away on its own when other beneficial bacteria/etc are able to outcompete it.
 

Rocks reef

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My response is far from critical. It is to the point and exactly the correct course of action. If you want to get very technical, sure Cyanobacteria is somewhere in the middle of algae and bacteria with characteristics of both. However, we are not phycologists trying to classify exactly where to place them on some chart. We are hobbyist trying to control their growth. If you want to follow advice the includes playing with nutrients based on inaccurate, low resolution hobby test kits that is your choice. It’s not that the kits are faulty, they lack resolution required to report levels that your eyes can tell you….you don’t have a nutrient deficiency problem.

Blow the stuff off and remove it, that is all that is required. Get some soft corals and start the reef going. Many soft corals are easier to keep than fish and you seem to have that figured out.
Clean the back wall and force your CUC to get their food from places that aren’t easy to clean. I would use a canister filter for a couple of hours to remove all kinds of crud. You can get one for about $50 on Amazon and any time you have a nuisance “algae” problem use it…
IMG_0948.jpeg
Again, you are wrong and coming off aggressive. He most certainly does have a nutrient issue.
 

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I will agree, it is a public forum and if I don’t want to be referred to I could just stay off. I don’t refer to posts i don’t agree with, I just give my “take”; I think it is a good policy. Nothing here online could offend me….

Regarding your advice, yes it is wrong. His back wall in complete covered with hair algae and he has multiple fish pooping and whatever. That stuff doesn’t, will not ever grow without abundant available nutrients. You can follow the current hobby mythology you learned from Joe Blow with some nice corals. Similar to how you can refer to me on a public forum, however, imo both are wrong.
It's not hair algae
 

Rocks reef

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It is a riddle….haha!

I was referring to the OP situation of zero nutrients and algae growth. In this case nutrients are available just below kits resolution. Personally I use LR Hanna for no3 which would absolutely read valves that no other hobby no3 test kit could.

IMG_0973.jpeg
The HR Hannah also reads that low... just saying
 

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And this is what Hanna says about their own HR Checker….not to great!

The HI782 was designed to quickly and easily measure nitrate levels for aquarists with higher-than-average nutrient levels. This includes saltwater aquariums that are fish-only or have corals that can tolerate elevated levels of nitrate at 30 ppm or more.
That simply means they designed that one to read higher than what the LR can. Plain and simple. You can use the HR to test low nitrates as well... ask me how I know?
 

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The HR Hannah also reads that low... just saying
Here is what Hanna says….sure you know more than them. Just saying….

The HI782 was designed to quickly and easily measure nitrate levels for aquarists with higher-than-average nutrient levels. This includes saltwater aquariums that are fish-only or have corals that can tolerate elevated levels of nitrate at 30 ppm or more.

Very low levels of nitrate are critical for many saltwater reef aquariums, as nitrate can cause damage and possible death to certain delicate corals and invertebrates. For this reason, the HI781 offers unmatched precision in the measurement of very low levels of nitrate (0.00 to 5.00 ppm
 

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He should work on increasing nutrients first... then the algae/cyano will go away on its own when other beneficial bacteria/etc are able to outcompete it.
This is a laughable comment, that goes against all science…..try the Matrix, might work there but not in reality.
 

Rocks reef

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Back track much?
No, not all frankly. I tested with both the LR and HR and got the same numbers... 1.14 to be exact, which is low for my tank. I will increase my ammonium dosing.
 

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This is a laughable comment, that goes against all science…..try the Matrix, might work there but not in reality.
Ok. Tell me then what causes dinos and/or cyano. Inquiring minds want to know
 

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Ok. Tell me then what causes dinos and/or cyano. Inquiring minds want to know

Forget about the myths in the glass box hobby and antidotal evidence common here, you might find this quote from above on point,
Cyanobacteria usually multiply and bloom when the water is warm, stagnant, and rich
in nutrients (phosphorus and nitrogen) from sources such as fertilizer runoff or septic tank overflows.”
 

Rocks reef

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Forget about the myths in the glass box hobby and antidotal evidence common here, you might find this quote from above on point,
Cyanobacteria usually multiply and bloom when the water is warm, stagnant, and rich
in nutrients (phosphorus and nitrogen) from sources such as fertilizer runoff or septic tank overflows.”
So you post an article about freshwater...
Ok, you obviously know way more about dinos, cyano and nutrients than some of the big names in the hobby. (Insert sarcasm at your own will).
I'm bowing out of this conversation for several reasons. First and foremost, you really do not know what you are talking about and are reluctant to listen or take consideration to the numerous posts on this thread that are factual.
 

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No, not all frankly. I tested with both the LR and HR and got the same numbers... 1.14 to be exact
Seems unlikely since the HR Hanna doesn’t go out 2 decimal points that is only the LR with that resolution, but maybe this happened in the Matrix too.
So you post an article about freshwater
obviously you didn’t read the article or lack understanding, referenced freshwater, brackish, and saltwater.
 

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Ok, you obviously know way more about dinos, cyano and nutrients than some of the big names in the hobby. (Insert sarcasm at your own will).
Just to clarify I have been in the hobby since 1980 when I worked at a LFS and kept sw tanks since 1982; however hobby observations has limitations. Most of what I’ve learned and practiced comes from reading and research, specifically Julian Sprung, and nothing I have claimed or recommended contradicts him…
 

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