Black Algae?

[Instigate]

Should I be concerned about this algae, I'm assuming, growth? Tank has been up for about 6-7 months, still going through the uglies. Some GHA, red and green cyano. Red cyano is growing slower than it was and I'm seeing more GHA starting here and there. The green cyano just showed up this week. I do feed heavy but my po4 is .25ppm and no3 is 1ppm. I noticed this black algae showing up about a month ago. I wasn't really concerned with it but I see it growing on top of some of the little spots of coralline algae now. So now I'm not too sure.

 

[Ocelaris]

Do you mean .025 or .25 phosphates? .25 is sort of high, I'd aim to get that down. I aim for .04 and mine hit .12 and I'm a little concerned, but if I was cruising at .25 I'd look for a long term way to bring that down. I'm only slightly less concerned about my .12 because I was bottoming out at .02 or less for a week, so it's a bit of an over correction.

Does it blow off like cyano? Color isn't really a big deal, but if it's hard to get rid of that may be an issue. Are you sure it's not red/maroon and your blue lights aren't distorting the colors?

Scrub scrub scrub! I use a turkey baster for diatoms, tooth brush for hairy algae... if it gets taken off the rock it usually decomposes.

 

[Instigate]

Do you mean .025 or .25 phosphates? .25 is sort of high, I'd aim to get that down. I aim for .04 and mine hit .12 and I'm a little concerned, but if I was cruising at .25 I'd look for a long term way to bring that down. I'm only slightly less concerned about my .12 because I was bottoming out at .02 or less for a week, so it's a bit of an over correction.

Does it blow off like cyano? Color isn't really a big deal, but if it's hard to get rid of that may be an issue. Are you sure it's not red/maroon and your blue lights aren't distorting the colors?

Scrub scrub scrub! I use a turkey baster for diatoms, tooth brush for hairy algae... if it gets taken off the rock it usually decomposes.

.25 on the salifert test kit. It's been stable there for about a month. Before that it was at .03 for a while. It looks black to me when the lights are off or on. Doesn't blow off like cyano. I have some clean chaeto from algae barn coming soon so when I start up the fuge that will likely drop. I'm just worried my nitrates will drop too. I'm hoping it will just out compete the cyano and gha and not drop my no3 too much.

 

[Ocelaris]

Usually phosphates will drop before nitrates, as their levels are usually a tenth or hundredth of nitrates. I would just scrub it off and see if you can reduce nutrients until you get your other nutrient reduction method in place. Do any of your clean up crew eat it?

 

[Instigate]

Hard to say. My cuc is only snails, nassarius and trochus as well as 2 cleaner shrimp. The black spots of what I'm assuming is algae isn't really hurting anything so I'm not too concerned with it. Curious if it's a known pest algae or something.

 

[Ocelaris]

Hard to say. My cuc is only snails, nassarius and trochus as well as 2 cleaner shrimp. The black spots of what I'm assuming is algae isn't really hurting anything so I'm not too concerned with it. Curious if it's a known pest algae or something.

I think people are overly optimistic on how much a clean up can do versus a string algae bloom. Either way, what's its characteristics, is is kinda like sandy? Diatoms kinda look like that, but usually brown.

 

[Benga]

I actually found some developing in my sump's LR lately. Very dark thick and slimy algae that only came off after brushing with a toothbrush. Couldn't be blown off with a baster or with my kitchen sinks spray function. My Turbo snails haven't been touching it either by the looks of it.

Here's a shot OP maybe it's similar to yours.

 

[Instigate]

I think people are overly optimistic on how much a clean up can do versus a string algae bloom. Either way, what's its characteristics, is is kinda like sandy? Diatoms kinda look like that, but usually brown.

Upon closer inspection they are a very dark brown under normal light. And the cuc are eating it. I forgot to mention I also have a couple emerald crabs. The crabs as well as the trochus snails are eating it.

I actually found some developing in my sump's LR lately. Very dark thick and slimy algae that only came off after brushing with a toothbrush. Couldn't be blown off with a baster or with my kitchen sinks spray function. My Turbo snails haven't been touching it either by the looks of it.

Here's a shot OP maybe it's similar to yours.

That's some ***** algae you got there. No, thankfully that's not what I've got.