Rust-colored patches growing on rocks

[Finless]

My tank is 8-month old biocube 29G.   In the past 3 weeks I notice these rust-colored patches spreading on the rocks.   Please help identify them and course of actions.

Thanks in advance.

 

Flow is from 2 Tunze 6040 mounted left & right, controlled by Apex

Filtration: Media Basket: Filter pad --> Seachem Phosguard --> Seachem Purigen  --> Tunze 9001 skimmer--> Return pump

Lighting is DIY LEDs with Bluefish mini controller.

6 Neutral White LEDs, 35% at midday

6 Royal Blue LEDs, 65% at midday

6 Blue LEDs, 65% at midday

This is the lighting profile from the app

 

tank parameters on 06/28/19 (Salinity: 1.026,  Temp: 78F)  Alkalinity is measured using Hannah & Salifert. 

 

Tank overall:

 

 

Rust-colored patch #1

 

Rust-colored patch #2:

[Joevember]

Looks like cyano or dinos to me.

[AJ69]

IMO, your tank is going thru a Dino cycle/bloom

[A.m.P]

... looks like cyano or some of the weirder looking diatoms/ nuisance algae to me, did you disturb your sand bed, rockwork, or add anything new recently? Or do you have deadzones/do you feed heavily? Try to manually remove some and see if it coagulates in a cup of water by itself or rapidly comes back. But just because it has bubbles doesn't mean it's dinos, that said it's hard to tell from your photos, you could try googling peroxide dosing if it continues to be an issue. And if it turns out to be dinos mccarrol has a thread on r2r for dealing with them.

[mcarroll]

Looks like your alk is a little all over the place.  Is that just testing noise or are you dosing anything, or...?

 

Phosphate and nitrate is probably a little on the two low side — the numbers I can make out are probably with in the air rate of your test kits so could actually be zero.   I would disable all of your excessive filtration and just leave nothing more than a protein skimmer running if you have one. You do not want to remove any more phosphates or any more nitrates.

 

Can you tell us what that algae is like? How does it feel, what does it do when you touch it or wave it off  the rocks?

 

If you can get a sample out of the tank with a little tank water, shake it up until the algae is in bits.  Then let it sit under a light for a while.  Dinoflagellates are the only thing that will regroup into a mass — every other allergy will just remain in bits.

[Ranjib]

Likely Dino. It’s normal , the tank is not matured yet. It’s common during the first couple of year. Keep on steady water changes. Having some flow at the bottom will help. Stabilize water chemistry, I.e. check if you are making the water too clean. What’s your feeding regimen ?

[mcarroll]

I forgot to ask about coraline algae.

 

It looks like there are spots of it on the back glass but they might be bleached.

 

Does the tank appear to be growing any Coraline algae now...or any algae besides this orange stuff?

[Finless]

Thanks for all the replies.

On 6/30/2019 at 7:17 AM, mcarroll said:

Looks like your alk is a little all over the place.  Is that just testing noise or are you dosing anything, or...?

 

Phosphate and nitrate is probably a little on the two low side — the numbers I can make out are probably with in the air rate of your test kits so could actually be zero.   I would disable all of your excessive filtration and just leave nothing more than a protein skimmer running if you have one. You do not want to remove any more phosphates or any more nitrates.

 

Can you tell us what that algae is like? How does it feel, what does it do when you touch it or wave it off  the rocks?

 

If you can get a sample out of the tank with a little tank water, shake it up until the algae is in bits.  Then let it sit under a light for a while.  Dinoflagellates are the only thing that will regroup into a mass — every other allergy will just remain in bits.

I tested alk using Hannah (H) and Salifert (S).   I'm dosing Bionic #1, #2 & Mag to keep pH within 8.12 - 8.24 all day/night.

I took the rocks out (broke few branches off the birds nest), and it felt a bit slimy.   I used a toothbrush to clean it off but cannot get all of it.

On 6/30/2019 at 7:21 AM, Ranjib said:

Likely Dino. It’s normal , the tank is not matured yet. It’s common during the first couple of year. Keep on steady water changes. Having some flow at the bottom will help. Stabilize water chemistry, I.e. check if you are making the water too clean. What’s your feeding regimen ?

I have mostly LPS now and starting to add few SPS so I'm trying to figure out what works.   I feed once a day, alternating between flakes, pellets, LRS, or frozen mysis + oyster eggs, reef roids or phytofeast every time.

 

On 6/30/2019 at 7:39 AM, mcarroll said:

I forgot to ask about coraline algae.

 

It looks like there are spots of it on the back glass but they might be bleached.

 

Does the tank appear to be growing any Coraline algae now...or any algae besides this orange stuff?

There are coreline algae starting to grow which I am happy to see.   The white dots look like tiny barnacles.  Why is it bleached?   Lights too high?

Here is the close up of the back

 

[mcarroll]

Probably bleached from the swinging alkalinity and magnesium.  The very-low nutrient levels may present a challenge for it as well.

 

Presumably it is not the lights since it appears that the coraline was able to grow well there for at least some amount of time.

 

Beginning immediately you have complete permission to not test or pay any attention whatsoever to your pH.  Under normal circumstances, which should be almost all the time, you should not have to pay attention to pH as it is dictated by alkalinity, which you are already testing.

 

From now on the alkalinity part of your ESV kit should be dosed only in response to an alkalinity test result. And the calcium part should only be dosed in response to a calcium test result.   The recommended dosing targets on the side of the bottle are fine.

 

BIonic's parts one and two actually carry the magnesium in them so you should not have to dose magnesium separately unless something is very out of whack. (They do sell separate and discreet calcium, carbonate and magnesium supplements for making these adjustments that are not part of every day dosing.)

 

If something is out of whack with your magnesium level, you should just have to do a single magnesium dose to bring the number in line with your testing target.  (Again pH is not involved in this testing or dosing.)

 

From the adjustment onward, two part dosing with B ionic alone should be sufficient with no more mag supplement needed.

 

 by the way, if you couldn't get that algae off with a toothbrush then it's definitely not dinoflagellates — something else.

 

I think it was mentioned already, this is probably just a phase of the uglies and nothing to worry about as long as you correct the environment that lead it to grow.  

 

By that I mean stabilizing the alkalinity, calcium and magnesium as well as the nutrient levels (that is, positive nutrient levels...not near-zero)  and upgrading your cleanup crew as needed and more importantly you being the cleanup crew as often as needed. 🙂 

 

 

 

 

[Finless]

Thank you for your information.  I'll follow your instructions and report back.