Cyano?

Hakon

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My tank is about three months old 38 gallons parameters normal for this early (I think) and I've been slowly working through a relatively mild ugly phase, I had a pretty gnarly bloom of what I think were diatoms to after I added my first fish post cycle, at first my initial batch of three hermits and 4 trochus snails dealt with it fairly easily but then after I upped the lights to my intended full power they came back with a vengeance, I added six more hermit crabs and a tiger conch and a small UV sterilizer to deal with a bacteria bloom.

What I'm seeing now is this patch of ochre red/brown stuff:

20251231_205926.jpg

Tiger Conch for scale

I'm guessing this is some sort of cyano, it's hard to see in the pic but it's got what look like little bubbles trapped inside the mat. I see a couple other bits of it here and there but only four patches and the next biggest one is like half that size.

Not too worried right now as it's taken maybe a month to get that size but wanted to see what people think.
 

rayadog

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You are correct. It should suck right off the rock. I try to get the bubbles first but it’s not 100% possible to get them all at once.
 

Uncle99

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My tank is about three months old 38 gallons parameters normal for this early (I think) and I've been slowly working through a relatively mild ugly phase, I had a pretty gnarly bloom of what I think were diatoms to after I added my first fish post cycle, at first my initial batch of three hermits and 4 trochus snails dealt with it fairly easily but then after I upped the lights to my intended full power they came back with a vengeance, I added six more hermit crabs and a tiger conch and a small UV sterilizer to deal with a bacteria bloom.

What I'm seeing now is this patch of ochre red/brown stuff:

20251231_205926.jpg

Tiger Conch for scale

I'm guessing this is some sort of cyano, it's hard to see in the pic but it's got what look like little bubbles trapped inside the mat. I see a couple other bits of it here and there but only four patches and the next biggest one is like half that size.

Not too worried right now as it's taken maybe a month to get that size but wanted to see what people think.
Parameters normal for this early…..what are they and how much flux?
 
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Hakon

Hakon

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Parameters normal for this early…..what are they and how much flux?
Nitrate .9 PPM
Phosphate 0.0 PPB
PH 7.68

Temp ~77-77.5 f

using Hanna testers for uniformity accross my tests.

I know I have to get the PH up so I haven't been considering coral or testing for Magnesium/Calcium/Alkalinity until I do, I was hoping I'd get some leaching from the raw marco rock I used over time while I dialed in my cleanup crew and lighting. Considering getting some Kalkwasser and dosing up my PH at this point though.

I haven't had much flux in parameters except for a downward trend, initial amonia spike followed by a nitrate spike that was up around 2.5 ppm and going down every time I do a water change, I've been considering slowing down on water changes since everything has been so quiet.

edit: probably helps that I'm on San Francisco water which is some of the cleanest in the country other than being very soft.
 

Dan_P

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My tank is about three months old 38 gallons parameters normal for this early (I think) and I've been slowly working through a relatively mild ugly phase, I had a pretty gnarly bloom of what I think were diatoms to after I added my first fish post cycle, at first my initial batch of three hermits and 4 trochus snails dealt with it fairly easily but then after I upped the lights to my intended full power they came back with a vengeance, I added six more hermit crabs and a tiger conch and a small UV sterilizer to deal with a bacteria bloom.

What I'm seeing now is this patch of ochre red/brown stuff:

20251231_205926.jpg

Tiger Conch for scale

I'm guessing this is some sort of cyano, it's hard to see in the pic but it's got what look like little bubbles trapped inside the mat. I see a couple other bits of it here and there but only four patches and the next biggest one is like half that size.

Not too worried right now as it's taken maybe a month to get that size but wanted to see what people think.
Why don’t you just suction the red patch off with a turkey baster?
 
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Hakon

Hakon

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Why don’t you just suction the red patch off with a turkey baster?
That's what I did as soon as someone else confirmed it was cyano, I just wanted to post and see what people thought before I acted, I've been out of the hobby for years and this is the first tank I've ever done with a dry rock biome cycle method, back in the day 10+ years ago it was wet live rock or nothing.
 

Dan_P

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That's what I did as soon as someone else confirmed it was cyano, I just wanted to post and see what people thought before I acted, I've been out of the hobby for years and this is the first tank I've ever done with a dry rock biome cycle method, back in the day 10+ years ago it was wet live rock or nothing.
Welcome back to the hobby! Is it as much fun as as before?
 
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Hakon

Hakon

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Welcome back to the hobby! Is it as much fun as as before?
I will say this is probably the smoothest start I ever had, I don't know if that's down to more modern products and methods or the fact that I'm much more patient than I was in my 20s. I'm at about three months and so far I've only slowly put in a pair of clowns and a crew of inverts and I'm only now starting to think about getting coral so that's different. The hobby is so much more expensive though.
 

Dan_P

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I will say this is probably the smoothest start I ever had, I don't know if that's down to more modern products and methods or the fact that I'm much more patient than I was in my 20s. I'm at about three months and so far I've only slowly put in a pair of clowns and a crew of inverts and I'm only now starting to think about getting coral so that's different. The hobby is so much more expensive though.
Yeah, the cost of things in this hobby can be stunningly high and so is the pace of stocking aquaria for some hobbyists. It seems you are setting a more reasonable pace. Also, I doubt modern products are playing as big a role in your success as you are.

Good luck!
 

Uncle99

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Nitrate .9 PPM
Phosphate 0.0 PPB
PH 7.68

Temp ~77-77.5 f

using Hanna testers for uniformity accross my tests.

I know I have to get the PH up so I haven't been considering coral or testing for Magnesium/Calcium/Alkalinity until I do, I was hoping I'd get some leaching from the raw marco rock I used over time while I dialed in my cleanup crew and lighting. Considering getting some Kalkwasser and dosing up my PH at this point though.

I haven't had much flux in parameters except for a downward trend, initial amonia spike followed by a nitrate spike that was up around 2.5 ppm and going down every time I do a water change, I've been considering slowing down on water changes since everything has been so quiet.

edit: probably helps that I'm on San Francisco water which is some of the cleanest in the country other than being very soft.
Zero (if actual zero) phosphate to me is a bad number as it’s an absolute requirement in trace amounts say 0.05-.15ppm and nitrate maybe just a hair higher at 3-5ppm.

All organisms use both and zeroes, (or way high levels) can favour faster growing pest bacteria and algae’s, like Cyano and Dino.

You could just directly bump phosphate, nitrate I’d just watch.

I have no concern with your PH. Hard to measure anyway.
 

mmorrison55

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For a more robust method incase you need to suction the whole tank at a some point.

1/2” silicone tubing (5 ft or however long you need to go from your display to your sump through a fine micron filter if you plan to reuse the water or to your drain) and some stainless “ bubble tea” straws off Amazon wrapped in a rubberband to fit tightly in the silicone tube makes a very sturdy cyano siphon.

Amazon product

Amazon product

Amazon product
 
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Hakon

Hakon

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Zero (if actual zero) phosphate to me is a bad number as it’s an absolute requirement in trace amounts say 0.05-.15ppm and nitrate maybe just a hair higher at 3-5ppm.

All organisms use both and zeroes, (or way high levels) can favour faster growing pest bacteria and algae’s, like Cyano and Dino.

You could just directly bump phosphate, nitrate I’d just watch.

I have no concern with your PH. Hard to measure anyway.
My guess is that the Phosphate levels are so low for a couple of reasons, first is that I used Marco Rocks premium shelf rock that was brand new to build my rock scape, from what I've read that stuff has a tendency to suck up phosphates for awhile after you start out. On top of that since the diatoms have died back I'm seeing green algae of some sort take over the rocks, I think it's either hair algae or bubble algae (too early to tell), I think if there were truly zero phosphates in the tank that stuff wouldn't grow more likely it's just eating it all and the test isn't able to pick it up.
 

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