Cyano Problem – Zero Nitrate, Low Phosphate

[CHSUB]

CHSUB, I curious what else you would suggest for GHA and a very tiny bit of cyano. My GHA doesn't seem to relent and I'm using manual removal with a cannister filter as you suggested. My Algae CUC is 2 urchins and about 10 snails ( they don't do much) and big tangs (hippo, wt brisltetooth, Purple) and a Foxface (large) and a Lawmower Blenny (Large).

Maybe scrubbing vigorously with a toothbrush….however I also have a very stubborn spot of what I would describe a GHA but more like turf. I scrub hard and some is removed but not completely and it grows back sometimes with air bubbles…that is completely annoying. I keep putting my snail directly on it and they eat some but not all. Ultimately corals will occupy that space but until then, I pretend it’s not there…haha. Here is a close up picture, you can see the air bubbles but soon that space will be gone. So adding corals will work too.

With Cyano, imo, it comes and goes. Just keep at it. I had a couple of spots a few months ago, now absolutely zero with no specific action taken.

 

[kingranch2003]

I see fish and algae, so basically toss your hobby test kit results because they are worthless.

I test often sometimes daily because I both enjoy doing it and seeing the results.

 

[CHSUB]

Thought I explained here…

…I was implying to use your eyes vs test kit results as a path to improvement.

 

[kingranch2003]

Thought I explained here…

Why do something daily and enjoy seeing the results of it if you also deem it worthless and say to toss it? How would one toss something And use it everyday?

 

[tbrown]

For clarification: I believe he said toss the hobby grade kits. Hanna is technically lab grade (only it's not really, just more accurate than some of the others?).

In the drinking water industry we use Hanna and Hach for most of our non-compliance sampling because they're verifiable results. For compliance we send the samples in to a lab because it is a more controlled environment with more frequently checked and calibrated equipment. The frequency of those lab tests being grossly different from our field tests was very low. I would imagine that most hobby grade tests are going to be "close enough" for most of our purposes. If I see blue on my phosphates test I know I'm not 0. Close enough. If I see pink on my nitrates test I know I'm not 0. Close enough. Alkalinity, Magnesium, and Calcium - close enough.

If I'm not chasing numbers, close enough is close enough.

Now, with that being said - phosphates I can't see on Salifert or Nyos or any other Phosphate test I've run until they're around the 0.25+. My eyes can't see that good I guess so I trust Hanna for that test.

 

[W31Olds]

Maybe scrubbing vigorously with a toothbrush….however I also have a very stubborn spot of what I would describe a GHA but more like turf. I scrub hard and some is removed but not completely and it grows back sometimes with air bubbles…that is completely annoying. I keep putting my snail directly on it and they eat some but not all. Ultimately corals will occupy that space but until then, I pretend it’s not there…haha. Here is a close up picture, you can see the air bubbles but soon that space will be gone. So adding corals will work too.

With Cyano, imo, it comes and goes. Just keep at it. I had a couple of spots a few months ago, now absolutely zero with no specific action taken.

Your Tank situation looks identical to mine except I don't have many Corals. I use a toothbrush and suck the Algae up with the filter. I don't want to resort to chemicals as it could stave out my Algae Blenny and Urchins. Flight 82, you could add a UV System. That can sometimes help and provides other benefits as well.

 

[CHSUB]

Why do something daily and enjoy seeing the results of it if you also deem it worthless and say to toss it? How would one toss something And use it everyday?

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.

 

[CHSUB]

Your Tank situation looks identical to mine except I don't have many Corals. I use a toothbrush and suck the Algae up with the filter. I don't want to resort to chemicals as it could stave out my Algae Blenny and Urchins. Flight 82, you could add a UV System. That can sometimes help and provides other benefits as well.

Just for visual, same system. No space=no algae.

 

[kingranch2003]

For clarification: I believe he said toss the hobby grade kits. Hanna is technically lab grade (only it's not really, just more accurate than some of the others?).

In the drinking water industry we use Hanna and Hach for most of our non-compliance sampling because they're verifiable results. For compliance we send the samples in to a lab because it is a more controlled environment with more frequently checked and calibrated equipment. The frequency of those lab tests being grossly different from our field tests was very low. I would imagine that most hobby grade tests are going to be "close enough" for most of our purposes. If I see blue on my phosphates test I know I'm not 0. Close enough. If I see pink on my nitrates test I know I'm not 0. Close enough. Alkalinity, Magnesium, and Calcium - close enough.

If I'm not chasing numbers, close enough is close enough.

Now, with that being said - phosphates I can't see on Salifert or Nyos or any other Phosphate test I've run until they're around the 0.25+. My eyes can't see that good I guess so I trust Hanna for that test.

I understood what he said. And I believe that's a big reason why I couldn't see it as anything other than a contradiction. Since the OP didnt mention what test kits he used, it just comes of as general disdain for them in general. Why are we assuming OP is using a sub par kit and not a Hannah also....

 

[CHSUB]

Why are we assuming OP is using a sub par kit and not a Hannah

Because very few use the LR Hanna. And if he was he would certainly get a reading, imo. The few that use the LR Hanna seem to always specify its use.

 

[CHSUB]

I understood what he said. And I believe that's a big reason why I couldn't see it as anything other than a contradiction. Since the OP didnt mention what test kits he used, it just comes of as general disdain for them in general. Why are we assuming OP is using a sub par kit and not a Hannah also....

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.

 

[W31Olds]

CSUB, I wish it were that simple for me. Add Corals to basically outcompete the Algae. But I don't want to add a bunch of Coral only to get it munched on. Flight, don't mean to highjack your thread, but I guarantee that once you beat Cyano, GHA will rear its ugly head. I figure my few Corals may be toast this week anyway because my Moorish Idol is finished QT and I also have an Emperor Angel that has been eyeing up my Duncans.

 

[tbrown]

CSUB, I wish it were that simple for me. Add Corals to basically outcompete the Algae. But I don't want to add a bunch of Coral only to get it munched on. Flight, don't mean to highjack your thread, but I guarantee that once you beat Cyano, GHA will rear its ugly head. I figure my few Corals may be toast this week anyway because my Moorish Idol is finished QT and I also have an Emperor Angel that has been eyeing up my Duncans.

Mine did. Got rid of Cyano, GHA showed up, now GHA is going away.

 

[CHSUB]

Why do something daily and enjoy seeing the results of it if you also deem it worthless and say to toss it? How would one toss something And use it everyday?

Your advice with my nutrients numbers pictured in May 2025? Hanna po4 and Salifert no3 both 0.00…

 

[kingranch2003]

Your advice with my nutrients numbers pictured in May 2025? Hanna po4 and Salifert no3 both 0.00…

What "advice" are we talking about?

There's a question mark in your comment, so I'm assuming your asking me something. Im just not sure what it is.

 

[CHSUB]

What "advice" are we talking about?

There's a question mark in your comment, so I'm assuming your asking me something. Im just not sure what it is.

I’m asking what advice you would provide me given the nutrients shown in the picture….

 

[kingranch2003]

I’m asking what advice you would provide me given the nutrients shown in the picture….

What do you need my advice on? Is there a problem that these nutrient levels are causing your tank? I'm not sure what advice I could give you. Here's some general stuff....

1. Invest in precious metals.
2. Placing contrasting color behind the Hannah checker would've made it easier to read (not a big deal)
3. Grow root vegetables because it's rewarding.

 

[larrysaltisfun]

Since this is a hijackable thread, I too have started a tank recently. It’s now about eight weeks old 210 gallon undetectable nitrates with hobbyists API and salifert. Low phosphates.. as previously mentioned by others in this thread I started with bad cyanobacteria/diatoms sucked those out weekly and now the beautiful hair algae has started. Brushing those with the best Oral-B I can find and sucking that out now Seems like advice is split between dosing ammonium and to keep on sucking. my LFS GUY of course is “that guy” with an amazing 900 gallon tank in his shop with incredible corals says to keep on sucking and don’t mess with nutrients while your tank is maturing.

PS I respect the comments of experts on reef2 reef It is amazing. The knowledge that is displayed and offered here.

 

[CHSUB]

my LFS GUY of course is “that guy” with an amazing 900 gallon tank in his shop with incredible corals says to keep on sucking and don’t mess with nutrients while your tank is maturing.

I 100% agree with this advice and would give exactly the same….

 

[larrysaltisfun]

I didn’t take your comment as harsh at all. They were just matter of fact and to the point and sometimes that’s what we beginners need to hear.