What is this black stuff in my tank?

[jigglypuff7]

I have a BW tank with this stuff growing in my tank. I've never had it before a couple months ago. LFS suggested it was a bacteria not an algae and to use an antibacterial in the water. I was wondering if anyone has seen this before and if its safe to use the antibacterial.
TY!!

[mrgreen]

The black dots or the white splotches?

[jigglypuff7]

Either one? the black stuff comes off really easily and grows on top of every surface. its like black blankets.

[Pufferpunk]

Cyanobacteria.

[dlowis]

I would take the plants and ornaments out rinse all that cyanobacteria off of them and then give them an hour or two bath in a gallon of water with a maracyn tablet the (active ingredient is erythromycin an antibiotic)(not maracyn2) crushed and dissolved into it, vacume the cyano out of the gravel clean the filter (only rinse the media in a bucket of aquarium water to keep up nitrifying bacteria) then rinse plants and ornaments off again and put back together. The point is to get as much cyano out as possible the erythromycin (maracyn) will destroy your biological filter. And when the cyano dies it is said to be toxic and adds to the bio load. I have read that low oxygen is a cause of cyano so you could check your filtration maybe add a fine bubble stone to your aquarium for a while to increase surface agitation (most of the oxygen in the water is dissolved through the surface of the water). I have also heard of cutting off your tank from light with black trash bags or dark towels for 3 or 4 days I have had it before and these are the types of things i do. I would only use maracyn in the tank if all else fails. hope this helps I got some info from james planted tank algae guide (google it) it says low nitrates are a cause also

[Pufferpunk]

There is a product called Chemiclean, which is safe to use & won't destroy your BB. Just be sure to clean out as much cyano as possible before using & use exactly as directed.

[jigglypuff7]

Ok im going to try the chemiclean and switch out my bulb & leave the light off for a couple days. PP do i need to redose with biospira at some point after this?
You are lifesavers! Thank You!

[Pufferpunk]

Nope, Chemiclean doesn't destroy your filter like other meds can.