NPS Sponge in Plumbing?

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Has anyone ever heard of an NPS sponge growing in plumbing? I would have thought the flow would be too much. But, I recently have had an issue with my overflow levels being inconsistent. Now, I have a Red Sea G2 so I thought it was just the diaphragm valve acting up yet again. So, I took it apart as much as I could and cleaned it and the problem continued. So I took a flash light and looked down the overflow pipe and it looked like there was a white NPS sponge covering part of the down drain. Anyone ever heard of that? The flow going through there is pretty fast so like I said, I wouldn’t have thought it possible.
 
Absolutely possible, I don't think the sponge minds the flow too much. There might be a lot of water passing through, but it always comes from one direction so the sponge can probably adjust.

Scraping it off will probably be insufficient to fully get rid of it. It most likely will regrow from tiny residues. Another possibility would be a bacterial mucus. This stuff can grow under very high flow as well and clog plumbing. Are you carbon dosing by any chance?
 
Absolutely possible, I don't think the sponge minds the flow too much. There might be a lot of water passing through, but it always comes from one direction so the sponge can probably adjust.

Scraping it off will probably be insufficient to fully get rid of it. It most likely will regrow from tiny residues. Another possibility would be a bacterial mucus. This stuff can grow under very high flow as well and clog plumbing. Are you carbon dosing by any chance?
I am carbon dosing with NP Bacto Balance. I didn’t think about bacteria, it could be that too. It’s situated just beyond my reach unless I completely
disconnect the plumbing. I thought about getting a snake and trying to break it up to deal with it. Even if I have to do it regularly for maintenance unless there’s another option.
 
I’ve definitely seen all manner of filter feeding organisms in plumbing, as is evident from my tank breakdown plumbing graveyard:

image.jpg


overflow boxes in particular get absolutely encrusted, but plumbing also gets its fair share of NPS filter feeders growing in it!

It’s situated just beyond my reach unless I completely
disconnect the plumbing. I thought about getting a snake and trying to break it up to deal with it.

— to clear plumbing on a operating tank, I typically just resort to disconnecting the plumbing subassembly from the tank in question, taking the subassembly outside, blasting it out with a garden hose sprayer, running a pipe snake through it, then blasting it out with the hose again before reassembling!

(The high velocity chlorinated fresh water does a fantastic job of loosening and flushing out any non-calcified organisms, and the pipe snake knocks anything calcified off mechanically before you flush with fresh water yet again, attempting to flush any remaining bits out prior to drip drying, and reassembly!)
 
I’ve definitely seen all manner of filter feeding organisms in plumbing, as is evident from my tank breakdown plumbing graveyard:

image.jpg


overflow boxes in particular get absolutely encrusted, but plumbing also gets its fair share of NPS filter feeders growing in it!

It’s situated just beyond my reach unless I completely
disconnect the plumbing. I thought about getting a snake and trying to break it up to deal with it.

— to clear plumbing on a operating tank, I typically just resort to disconnecting the plumbing subassembly from the tank in question, taking the subassembly outside, blasting it out with a garden hose sprayer, running a pipe snake through it, then blasting it out with the hose again before reassembling!

(The high velocity chlorinated fresh water does a fantastic job of loosening and flushing out any non-calcified organisms, and the pipe snake knocks anything calcified off mechanically before you flush with fresh water yet again, attempting to flush any remaining bits out prior to drip drying, and reassembly!)
Thanks. I’ll get give that a try tomorrow.
 
Agreed, chlorinated water will probably be your best bet if they are sponges since they're not calcified.

However, be very careful to not get any bleach into your system. 10-50ppb (not parts per million, parts per billion!) free chlorine can kill your fish. I've learnt this the hard way.
 
However, be very careful to not get any bleach into your system. 10-50ppb (not parts per million, parts per billion!) free chlorine can kill your fish. I've learnt this the hard way.
Can you elaborate?
 
Can you elaborate?
Very little bleach + water = fish gill damage

I bleach sterilize all aquariums in our facility in-between shipments if disease is found. I was previously using a spray bottle to save on bleach, but I suspect a few droplets got into my 50 gallon RODI storage and was later what might have killed off an entire shipment. It was undetectable by regular drinking water test kits. I now use a Hanna low range chlorine test kit to ensure this doesn't happen again.

To be honest I have no proof that it was due to the bleach, but this is quite well documented. You only need ~0.02mL of regular 8% bleach in 50 gallons to get to levels that cause very severe gill damage. Jump to pdf page 106 and 107:
https://www.afcd.gov.hk/english/quarantine/qua_vetlab/files/common/PCFinHK.pdf

It is the same reason why you must have catalytic carbon if you are reefing in a city that uses chloramines.
 
Very little bleach + water = fish gill damage

I bleach sterilize all aquariums in our facility in-between shipments if disease is found. I was previously using a spray bottle to save on bleach, but I suspect a few droplets got into my 50 gallon RODI storage and was later what might have killed off an entire shipment. It was undetectable by regular drinking water test kits. I now use a Hanna low range chlorine test kit to ensure this doesn't happen again.

To be honest I have no proof that it was due to the bleach, but this is quite well documented. You only need ~0.02mL of regular 8% bleach in 50 gallons to get to levels that cause very severe gill damage. Jump to pdf page 106 and 107:
https://www.afcd.gov.hk/english/quarantine/qua_vetlab/files/common/PCFinHK.pdf

It is the same reason why you must have catalytic carbon if you are reefing in a city that uses chloramines.
Free chlorine can obviously damage gills, but small amounts of bleach in a tank don't have to be a problem. Your source describes permanent exposure at a measured concentration, but if you dose a theoretical amount of "0.1ppm free chlorine" into your tank once, a good part of it reacts with organics and trace elements before it reaches the fish.

"The recommended safe long-term exposure level is total chlorine < 0.003 ppm (ANZECC, 2000). Total chlorine levels ≥0.1-0.4 ppm have been associated with fish kills (Langdon, 1988) for freshwater species and ≥0.128-0.250 ppm for marine species (ANZECC, 2000)." - Page 193 (105/123 in your PDF)

0.02mL of 8% bleach in 50gal is only about 0.01ppm free chlorine, so below the levels that actually killed fish in the linked article, but above levels that would be considered safe during long-term exposure.

Bleach dosing is a thing... It's certainly weird (and certainly not the best thing you can do), but it's a thing people do. Bleach reacts quickly with organics and trace elements, so free chlorine drops fast. It does form some nasty compounds, but it won't nuke the tank when bleach is allowed to drop to safe levels again, so I think your shipment had other issues 🙁.

Many people here clean their filter socks with bleach and put them back in the sump unrinsed. A decently sized tank's chlorine demand should be high enough to handle it. So I don't think you accidentally killed your shipment with a few droplets and OP has no reason to worry about a tap-water-rinsed pipe 🙂
 

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