Black stuff

[StingrayKid]

My sandy substrate has turned black in a spot. What is this?

 

[Nix]

Dead spot

 

[StingrayKid]

What is a dead spot, and will it hurt my fish?

 

[StingrayKid]

I kinda smeared some of the dead spot around the tank. But seriously, will it hurt my fish?

 

[Katie]

you might as well have not bothered Nix if you're not going to explain what it is
i don't know what it is and i don't know if it's harmful but it's pretty mean saying a name like that and not going into it further.

 

[clutterydrawer]

I *think* it's where anaerobic bacteria have formed due to a patch of the sand having no oxygen reaching it. I read on this forum a few days ago that when these bacteria come in contact with oxygen (eg in the water of your tank!) they die which produces ammonia. So if that's true, you might want to test for ammonia and do a water change if there's increased ammonia levels.

How deep is your sand? You can prevent these dead spots from forming in future by stirring the sand up with a chopstick or something similar every now and then.

I don't know if I've been any use but it didn't look like anyone else was gonna reply.

 

[StingrayKid]

It's okay now, thanks for the help!

 

[Tropjunky]

like clutterydrawer said dead spots are patch sof sand that hasn't got any oxygen but its not dead bacteria i think it's an anarobic bacteria and yes yes do harm fish cos they produce a toxic gas and u can reduce them buy stiring the sand but also by thining out the sand ur sand should be about 1" ish but the best method i find is getting some bottom feeders (anyting to get more fish)

But i don't think u have dead spots it might be algee that looks black. but then why take a risk

 

[clutterydrawer]

But i don't think u have dead spots it might be algee that looks black. but then why take a risk

If he has black spots in his sand it is likely to be dead spots, the "blackness" is caused by hydrogen sulphide, nasty stuff.

 

[StingrayKid]

But, if I clean it out mostly, will it still harm them?