Black dust in sand.

[Boy]

My aquarium hasn't had any TLC for quite a while, about a year, Im trying to clean it back up but when moving the sand i noticed that the sand is black underneath and smells. I have about 3-4 inches of sand in my tank and about 1/2" below the surface of the sand there is this black dust that clouds the aqaurium when stirred. Im pretty sure its just decomposing waste, but what do you recommend i do as far as trying to clean things up. I still have some coral and fish alive in the aqaurium, but all the clean up crew is dead.

As for a reference to the black dust in the sand its similar to the dirty/stinky sand in some areas of corpus.

[Mike]

It is probably anaerobic bacteria (dead) which is not good. If you try to stir it up or clean it all at once, you will most likely have a small tank cycle, which can kill your fish and coral (cycle like when you 1st start a new rank). Maybe try cleaning it in small sections, every week.

Your sand bed is probably too deep. Not deep enough to be a DSB, but too deep for a normal display. Maybe try removing some a little at a time. CUC can help stir and keep your sand bed clean. HTH.

[justahobby]

You have entered the anaerobic compost pile. Check your water parameters and make sure you didn't get any spikes. It would be best to remove all livestock before tampering with the bottom of the sand bed.

[ErikH]

How big is your tank? I used to routinely run my fingers through the sand on my 75 in a combing action, 2 rows per week from front to back. I would keep adding CUC, and reduce or raise the sandbed depth.

[Boy]

What is CUC?
If i make the sand bed deeper, will that just cover up of problem or will it solve the problem? And how deep do i have to go?
If i lower the sand bed shold i be aimming for the 1inch mark?

[Mike]

CUC- clean up crew.

[allan]

If you reduce one inch is what you're looking for at the outside edge. You can go a little thinner if you like. As far as how deep, I think the general consensus is six inches.... there are others here that can comment on that.

A year of neglect and you still have some stuff alive seems to me that you have the touch to keep things alive... which is good.

Some of your questions stir a few of my own.

What is your goal?
What do you want to grow/keep?
What size tank are we talking about?
Do you run any kind of external filtration? What?

Each of these questions are forks in a road that lead to other questions and/or answers.

I'm not an expert, but if you would like to pick my brain you can give me a call and I'll entertain you for a few to see if we can come to an idea of where you want to go with this. I would recommend that you document here your questions though as all of this will provide answers for others that come later.

Your call, brother

[Boy]

What is your goal?
I really just want to clean it back up and get rid of the red slime and hair algae that has begun to take over.
What do you want to grow/keep?
I think im going to stick with zoas, since they are easy to maintain.
What size tank are we talking about?
Its a 50 gallon, nothing that big.
Do you run any kind of external filtration? What?
Well i have the regular old bio ball sump with an over flow. The about i month ago i added a hang on the back bio wheel filter hoping it would help clean the water.


I've done a couple water changes here an there but nothing other then that. I have managed to keep some sps and zoas alive but i've lost alot. An my tank is littered with my dead CUC.


Im going to begin with dropping the depth of the sand bed an buying parts of a CUC

[allan]

Beware a sudden drop in your sand level. You will definitely want to do this in small steps over time to limit the cycle you will most likely experience.

You're filtration should be good then, especially if you plan on sticking with the softies... But I'd look into some of the other filtration methods than the bio wheel and bio balls, the latter of which I hear become notorious nitrate factories. You can add some macro to a chamber and help with filtration as well, if you have the room.

You running T5s, LEDs or metal halides? How long has it been since you've replaced your bulbs?

Before you start working on a CUC, do some research. There are like three schools of thought that I have run across. No crabs, only crabs, and a mix. Crabs can be a source of angst as they tend to knock things over in their travels through your tank. IMO snails simply do not get all of the detritus that the crabs can get to. And they're fun to watch.

Keeping it simple will definitely make your life easier.

[allan]

The hair algae may be starting due to over used bulbs... there are other factors as well, but old bulbs tend to assist in nuisance algae.

[Boy]

Lol! Maybe i should have check the site before i started; I already drop the level of the sand. The tank was all black for about an hour, but the one clown i have is still alive an the coral seem okay. Seems like the next step would be to re-position the powerheads, then smooth out the sand dunes i have in the tank right now.
After that i think im going to go with a hermit/snail mix, hermits to maintain the rock work and snails for the sand an glass.

As for the bulbs i do think they are the cause of the algae, i noticed that my timer may have not been turning out the lights when im out to work.