What is this brown dusty stuff?

[Epiphanaea]

Google is failing me.  

[Fish Folk]

My guess is: MULM. In a sense, it is a sort of detritus -- though various aquarists will take offense at that conflation.

It is a fascinating set of organic matter that is generally loaded with micro-life. Unfortunately, the bacteria content is generally so high that benthic fish (e.g. Corydoras, Loaches, etc) that swim through it constantly become susceptible to infections. Fish such as Discus are very sensitive to infections because of their mucus slime coat.

I've had this situation before. I do not consider it necessarily harmful. But it is a mixed bag. Certain aquarists will swear by mulm -- I've even seen it for sale (e.g. LRB Aquatics). I recommend gently gravel vacuuming it up. Here is an excellent article to read all about it.

[Galabar]

What type of filter are you using?

[Epiphanaea]

On 8/10/2023 at 12:20 AM, Galabar said:

What type of filter are you using?

It’s an Aqueon hang-on-back, but with Matrix media, and some cut-your-own mat stuff, and some wadded up Viva paper towel (this was an accidental discovery but I swear this stuff is amazing for fine particulate matter).  

[Epiphanaea]

On 8/9/2023 at 9:15 PM, Fish Folk said:

It is a fascinating set of organic matter that is generally loaded with micro-life. Unfortunately, the bacteria content is generally so high that benthic fish (e.g. Corydoras, Loaches, etc) that swim through it constantly become susceptible to infections. 

So for Borneo loaches, no good?  I was hoping they might munch on it.

[Biotope Biologist]

I have found a topical ointment that is safe for all aquatic animals. It reduces redding and fin damage. 
 

My gobies are fairly aggressive diggers. And sometimes appear in the morning with torn fins or red heads.
 

API fin and body care

 

It was rather hard finding topical stuff that wouldn’t effect my shrimps or snails. Open sores can get infected especially from those fish who burrow or dig. So having this stuff on hand or something similar will help. I dose the main tank, doesn’t effect plants either. Also mulm is healthy. When it gets real bad I suck it into a watering pail to feed the garden.

[Fish Folk]

On 8/10/2023 at 10:52 AM, Epiphanaea said:

So for Borneo loaches, no good?  I was hoping they might munch on it.

I do not know the species well. Just do some careful research.

[TOtrees]

have you used any flocculants, like seachem stability? these are additives that cause small particles to glom together into bigger particle clusters. the aim is to then capture them via filtration. 

what sort of filtration do you have running, and how much flow? If I had that accumulation of detritus/mulm, I'd increase circulation to keep the junk moving around, and use a filter that can capture and remove it (eg filter floss in a HOB that can be discarded and replaced daily until water clear; or a sponge filter that can be rinsed repeatedly until water clears). another option is a herd of cories to constantly disturb and resuspend the bits. 

and feed less. not saying you're overfeeding, but it's a likely cause, and it's also a variable you can control (ie reduce feeding for a week or so and see if the amount of detritus/mulm diminishes). 

[Lennie]

I have borneo loach and they are %99 of the time are on glass or rock/driftwood. Cories are basically almost always on the bottom. I wouldnt worry about borneo sucker really

[Galabar]

Maybe you need more flow.  What exact filter are you using and what size tank?  You might try a powerhead to move debris out of dead spots: https://www.amazon.com/Aqueon-Circulation-Pump-Aquariums-500/dp/B07L1G321W

[Chick-In-Of-TheSea]

 

[Rube_Goldfish]

On 8/10/2023 at 11:47 AM, TOtrees said:

have you used any flocculants, like seachem stability?

I'm sorry to be That Guy, especially on a good post as this, but just to avoid confusion, Seachem's flocculant is Clarity; Stability is their bottled beneficial bacteria.

[Epiphanaea]

Combining replies - Aqueon Quietflow 20, tank is a 20L, I have the water level about 2” below the filter outflow to create a waterfall effect so there is pretty good water movement / oxygenation.  Contains Matrix, filter padding sponge stuff? (Not sure what to call), Viva paper towel (so basically fine wood-based cloth).  It is in the left rear corner of the tank, as dictated by where the openings are in the hood.  
 

Lighting is the standard white LED that came with the hood - planning to replace that, but haven’t yet.
 

I did use Seachem Stability to start the tank cycle.  It’s been set up ~4 months, took almost 2 to cycle.  Room temp, which is about 70F.

Substrate is a layer of fluval black sand, topped with thin layer of all-purpose sand.  The fluval was not rinsed - lesson learned there!  The all-purpose sand was.  There are also river rocks, covering ~1/3 of the bottom.

 There is a piece of driftwood ~18”x2-3”that was locally collected and steam sterilized before going in the tank, wood species unknown (just based on local flora, sycamore or maple are strong possibilities.  Not oak, I’d recognize that grain.)  No staining of the water and it took forever and a day to water-log even glued down.  It may be shedding some fibers, likely contributing to the mulm.

Plants are a tiger lily of pretty good size, some small leafy plants whose species I forget (two tissue-culture-from-PetSmart packages worth), a handful of moss, and some duckweed that is primarily serving as a pre-filter media because it gets stuck to the intake but seems to thrive there so okay then.  
 

There is black beard algae on the wood, has been slow to grow.  The water has a slight green tinge like there may be floating micro-algae, but it is clear, not cloudy at all.  No other algae despite efforts to start it.  
 

Occupants are a fluctuating population of small bladder snails (I keep scooping them out and transferring to the goldfish tank), one quarter-sized mystery snail who seems to be thriving, one pea-sized ramshorn snail, some small white crawly things that I think are (were?) planaria, but they seem to have disappeared so either it was inhospitable to them or the snails ate them.  There was briefly a damselfly larva (hitchhiker on the duckweed), but it died - I think it didn’t have sufficient room above water to shed and metamorphosize, my bad.  Everybody eats algae wafers provided about once a week.  It takes a few days for the wafer to be fully consumed.
 

For approximately 24 hours there were two kinda sickly Borneo loaches found mislabeled at Petco, but they didn’t make it.  I did transfer some moss-covered rocks in from the goldfish tank, and sprinkled in some Repashy over the rocks, but I think they were ill already (there was a dead one in the Petco tank) and never ate.  

 

[TOtrees]

On 8/11/2023 at 11:15 AM, Rube_Goldfish said:

just to avoid confusion, Seachem's flocculant is Clarity; Stability is their bottled beneficial bacteria.

yep. not going to change my post above, since i always find it confusing to see a reference to a comment that no longer exists, but thanks @That Guy for the correction. 😛

[Epiphanaea]

That’s with a small improvement in lighting as of today, had a bar light that didn’t work out for the betta tank so stuck it to the underside of the lid.

[RennjiDK]

On 8/10/2023 at 7:16 PM, Chick-In-Of-TheSea said:

 

In order to get the sort of gyre effect he's describing in the video, you need massive flow. I doubt that it could be done practically in a FW system, and certainly not from a HOB. Realistically, when the water exits a HOB, it just slowly pushes across the surface until it reaches the glass, then changes direction. Even if the water level is below the output (waterfall), there will be small eddies that form around the exit point, but the energy quickly dies off in the surrounding water volume. That's why floating plants end up in one corner, or going around in circles all day.

[RennjiDK]

On 8/9/2023 at 7:53 PM, Epiphanaea said:

Google is failing me.  

I would personally try to vacuum out as much as possible during a WC. I would just use the hose itself, unattached from the plastic tube of your python for more flow. Once the bulk is removed, you could try a product like Dr Tim's waste away. I don't particularly like his brand and normally don't recommend it, but it's worth a shot.