Dark velvet like algae ID/treatment?

[Necrodaemus]

Anyone know what this stuff is? It’s dark brown (appears black under blues) and forms a dense (a couple millimeters thick) peach fuzzy/velvety mat over a lot of the upper rocks. I can pick it off with a sharp dental pick but it takes a lot of work (it’s somewhat soft but pretty ‘caked’ on). First pic is under my typical blue schedule, using an orange filter and second pic is with whites turned up.

 

[Lavey29]

Maybe some form of turf algae? What is your tank age and parameters? What cleaners do you have?

 

[Necrodaemus]

Maybe some form of turf algae? What is your tank age and parameters? What cleaners do you have?

Tank is 9 months old, started with dry white rock. CUC is multiple hermits, trochus snails, chitons, keyhole limpets, dwarf cerith snails, fighting conchs, nessarius snails, and a tuxedo urchin.
Parameters are:
8.5dKH, 430Ca, 1350Mg, NO3- 2.5-5ppm, PO4- 0.02-0.05ppm.

 

[Lavey29]

Tank is 9 months old, started with dry white rock. CUC is multiple hermits, trochus snails, chitons, keyhole limpets, dwarf cerith snails, fighting conchs, nessarius snails, and a tuxedo urchin.
Parameters are:
8.5dKH, 430Ca, 1350Mg, NO3- 2.5-5ppm, PO4- 0.02-0.05ppm.

Numbers seem good. Nitrates slightly low. My dead rock did turn brown like that for a few months during the first year and then went away on its own. Are you runn8ng a fuge? Do you dose phytoplankton daily and have pods? I also use PNS probio which is a heterotrophic bacteria that eliminates organic waste.

Any lighting changes recently?

 

[Necrodaemus]

Numbers seem good. Nitrates slightly low. My dead rock did turn brown like that for a few months during the first year and then went away on its own. Are you runn8ng a fuge? Do you dose phytoplankton daily and have pods? I also use PNS probio which is a heterotrophic bacteria that eliminates organic waste.

Any lighting changes recently?

No refugium as it’s an AIO but I recently placed a piece of plastic mesh canvas and a submersible grow light in one overflow to see if I can get turf to grow on it (as a means to try and outcompete this stuff). I have a lot of amphipods but haven’t seen any copepods in the tank since dosing some months ago. I do dose live phyto but admittedly I slacked off for several months and recently started again. I considered dosing MicroBacter7 again but afraid it will reduce nutrients even further and risk dinos/starving corals of PO4.

 

[Lavey29]

No refugium as it’s an AIO but I recently placed a piece of plastic mesh canvas and a submersible grow light in one overflow to see if I can get turf to grow on it (as a means to try and outcompete this stuff). I have a lot of amphipods but haven’t seen any copepods in the tank since dosing some months ago. I do dose live phyto but admittedly I slacked off for several months and recently started again. I considered dosing MicroBacter7 again but afraid it will reduce nutrients even further and risk dinos/starving corals of PO4.

Microbacter clean works better on rocks but you are correct it will reduce nitrates so you need to monitor it. I would dose it maybe once a week. Get a jar or two of Tigger pods and dose phyto. Try to manually remove what you can with weekly water changes. Stay the course and it will pass in a few months like mine did.

 

[Necrodaemus]

Microbacter clean works better on rocks but you are correct it will reduce nitrates so you need to monitor it. I would dose it maybe once a week. Get a jar or two of Tigger pods and dose phyto. Try to manually remove what you can with weekly water changes. Stay the course and it will pass in a few months like mine did.

Thanks for the tips! Hopefully the pods will survive…I have a sixline wrasse that has eliminated all but the amphipods that hide until night. Had flatworms on several LPS and haven’t seen any in months.

 

[Lavey29]

Thanks for the tips! Hopefully the pods will survive…I have a sixline wrasse that has eliminated all but the amphipods that hide until night. Had flatworms on several LPS and haven’t seen any in months.

I have 5 wrasses including a 6 line and also a mandarin but my tank still has pods. See them darting around at night on the sand. I drop a small bottle in monthly and my fuge has a variety of copepods and amphipods.

 

[jtdesigner]

I have sort of the same stuff, and it’s driving me nuts. It looks like coralline algae, except that it’s black. Not fuzzy or velvety, just black. It’s spread all over my live rock and choked out every single coral within a matter of weeks. I’ve done nothing new in my maintenance, my water is fine, fish are all healthy, and all the corals were all growing nicely when all of a sudden it appeared.