Stringy Algae?

[hiseabird]

I am starting up my 3rd 'opae tank right now to upgrade my babies. My 20 shrimp from Mustafa 2.5 years ago have turned into several hundred in a 2.7gal and a .9gal - pretty much don't feed either of those (maybe 2x/year?) and they are all doing great and having babies left and right. (The tiny tank just had two berried shrimp release their larvae this week!)

So I've got a 5gal tank with coral sand starting to cycle right now - did the standard making brackish water instant ocean at 1.01 sg. I did add some macroalgae and water from the existing tank, with a few snails, and a few chips of spirulina shimp food to keep the snails happy until the algae really gets going. I'm heading out to find some good lava and coral rocks tomorrow to add in and let algae start growing on them (I live in Hawaii and can find beautiful dead coral and holey lava rocks by the coast).

Here is the maybe-problem ... It's now been about a week and I'm seeing biofilm on top, but in the last few days, I've noticed some really weird long stringy ... algae? It looks like a spiderweb underwater and has some sand and macroalgae suspended in it. Is this something I should be worried about? Or just let it keep going and it will all even out? Thank you in advance for the help!

[mike.d]

It might be hair algae. If you reach in and touch it, is it really fine and slimy? If so, it's probably hair algae. I end up with a crop in my tank every year or so. I pluck out as much as I can with aquascape tweezers. I've noticed it grows more slowly in brackish water than it did in my freshwater tank.

[Super Jess]

I had that when I started my first tank, and never did figure out exactly what it was. It disappeared after a week or so.

[hiseabird]

I can't even seem to really touch it - it just disintegrates. I'm waiting a few more weeks anyways to cycle and get good algae going before I add shrimps, so I'll wait and see. Hopefully it will also go away on its own. Thank you!

[Super Jess]

Consensus at the time seemed to weigh towards a slightly unusual occurrence of snail slime or microorganism secretions. I had prepped my small tank with snails and macroalgae to help it cycle well before adding the shrimp. It disappeared well before my shrimp arrived. Here's what mine looked like:

[ssdarling]

It looks to me to be cyanobacteria. It happens in new tanks but usually resolves itself.