I have a 100 gallon reef system up 10 months. Just a few soft corals, 3 shrimp, and 5 small fish. I had a bad outbreak of GHA which is starting to die back. All water parameters very good. I dose 1 ml vodka per day and run GFO in a homemade reactor. I also have a cup of carbon in a bag. A few weeks ago I noticed my filter socks turning black. It washes out but they become black very quickly. Within hours. I put a prefilter under the sump incoming water and it turns black also. I run a DIY airstone skimmer which works as it should but it too is black. Is this dead algae or does it have something to do with the vodka dosing? Nitrates and phosphates near 0. Ph 8.2 1.35 salt
filter socks turning black
- Thread starter Jeff Murray
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W1ngz
Failed Padawan
What's the flow like through the carbon? Could it be that it's churning and being ground up and creating dust/powder? Try pulling it out for a day or two and see if the problem continues.
W1ngz
Failed Padawan
You might also consider a close inspection of anything magnetic on the glass like frag racks, algae clips or glass scrapers/cleaners to make sure the magnets haven't become exposed to water.
Peace River
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Is there a chance that it could be the carbon? Did you rinse the carbon before you put it in the system?
+1 to @W1ngz, if the carbon was initially rinsed then it could be breaking down. Good luck!
Carbons clean. This is a huge amount of black gunk. Water is crystal-clear . It looks like decayed matter so I was assuming dead algae but it seems to be
Carbon is clean and water is crystal clear.. It seems to look like decayed matter but I have no idea where its coming from. Throat of skimmer and cup is black as is skim mate. Socks turn black on upper edge within hours. Not overfeeding and skimmer produces very little foam. I also have an algae scrubber which is covered in a black algae. Doesn't grow hair or green algae. Could the gfo cause it?
Carbon is clean and water is crystal clear.. It seems to look like decayed matter but I have no idea where its coming from. Throat of skimmer and cup is black as is skim mate. Socks turn black on upper edge within hours. Not overfeeding and skimmer produces very little foam. I also have an algae scrubber which is covered in a black algae. Doesn't grow hair or green algae. Could the gfo cause it?
Nothing metal in tank except two powerheads
Peace River
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Your description of black slime algae makes me think cyano. Do you have any pics?
W1ngz
Failed Padawan
If you're sure it's not the carbon and don't want to remove it, it's possible that it's really dark cyano. In freshwater i've seen black algae but I'm not aware of anything like that in saltwater. Maybe it's some kind of mould? Dead algae usually just breaks down into a brown goo and dissolves into the water column until it turns the socks brown.
W1ngz
Failed Padawan
You can see the dust in the sand also. I'm going back to my original suggestion to remove the carbon.
Siphon the sand, pull and clean the whole skimmer, replace the sock and filter pads, let it run a couple days and repeat the process to clear out what remains in the plumbing or elsewhere. Clean out all the pumps in case perhaps one or two granules ended up in there and are being ground up by an impeller.
Siphon the sand, pull and clean the whole skimmer, replace the sock and filter pads, let it run a couple days and repeat the process to clear out what remains in the plumbing or elsewhere. Clean out all the pumps in case perhaps one or two granules ended up in there and are being ground up by an impeller.
I pulled the carbon. It is slimy not gritty at all. The thin coat of algae growing on the scrubber was very dark and slimy too. The sand in the tank has a few patches of light brown but not black. If it was that much carbon sloughing off you would think I would see it suspended in the tank water and on the bottom of the sump. Ill run without it for a few days and see what happens. Thanks for your advice.
