Fuzzy white mold?

AthensReef · Nov 28, 2019

Hi all,

I can’t seem to find any information as to why the water line of my in-cabinet sump is developing mold, or at least it looks like mold to me. It’s growing along most of the waterline in the sump only. It’s also growing some in the rear sump (Red Sea E260).
Any ideas??

ahiggins · Nov 29, 2019

Bump and following-I have some of this on my lid.

AthensReef · Nov 29, 2019

ahiggins said:
Bump and following-I have some of this on my lid.

This seems to be a fairly uncommon problem, searched and found very little info. Wipes off easily, just not sure if something with my water conditions could be causing it??

Bryknicks · Nov 29, 2019

I'm thinking it's a sponge. Has this tank been established a while?

TheShrimpNibbler · Nov 29, 2019

This is actually pretty common. You stuck a tank in a closed cabinet, so it’s gonna get pretty moist and humid in there. When it gets moist, mold grows. It’s not a problem. Just wipe it off and wait for it to come back.

ahiggins · Nov 29, 2019

Well alrighty then. Mines on the underside of my lid though

TheShrimpNibbler · Nov 29, 2019

ahiggins said:
Well alrighty then. Mines on the underside of my lid though

Sorry, i didn’t mean to come off as rude and that wasn’t my intention at all. I didn’t realize how badly I had phrased my post.

ahiggins · Nov 29, 2019

Oh no lol i didn’t take it that way. It was more like “well crap, that’s a boring answer. Guess I’ll have to start oartrolling for mold now” lol and “let’s hope it never falls into the tank”
You were just fine

I technically hijacked OPs thread anyway, having the same junk

AthensReef · Nov 29, 2019

TheShrimpNibbler said:
This is actually pretty common. You stuck a tank in a closed cabinet, so it’s gonna get pretty moist and humid in there. When it gets moist, mold grows. It’s not a problem. Just wipe it off and wait for it to come back.

I agree with you, just seems odd it started now. Tank has been running for several months. Also, it’s growing in the rear sump, it’s an AIO tank. No cover to hold in moisture.

TheShrimpNibbler · Nov 29, 2019

AthensReef said:
I agree with you, just seems odd it started now. Tank has been running for several months. Also, it’s growing in the rear sump, it’s an AIO tank. No cover to hold in moisture.

I would guess that it’s been there for a while, but just recently got to a large enough size that you can see it. You wouldn’t be able see the spores.

AthensReef · Nov 29, 2019

TheShrimpNibbler said:
I would guess that it’s been there for a while, but just recently got to a large enough size that you can see it. You wouldn’t be able see the spores.

Gotcha, maybe I’ll throw a small fan in the sump area to move the air around. I’m just concerned if it falls in the tank it could cause problems, on top of being unsightly. Thank you for the replies!

reeferdugong · Mar 23, 2021

hi guys, sorry to bump old thread. I seem to have this as well. Nothing to worry about right?

Joe31415 · May 23, 2021

Bumping this again. I have the same issue. I get some along the water line (both in the DT and sump) but the place I seem to notice it the most is around the rim, both above and below the lip.

I wipe it off with a wet paper towel from time to time, but it grows right back.

Right now, the tank is empty and waiting for it's first inhabitants to get out of their QTs. So I'm thinking I'm going to wipe it all off and then hit all those areas with ammonia*. And since I already have an AWC up and running, it can take care of removing any mold that gets knocked into the water or excess ammonia.

*or vinegar, but ammonia seems like it makes more sense. Any that ends up in the water will just keep the bacteria fed.

fachatga · May 23, 2021

That last pic kind of looks like salt to me. Water gets on top of that ledge and evaporates leaving the salt. Pic isn’t crystal clear though so I could be wrong.

Joe31415 · May 23, 2021

fachatga said:
That last pic kind of looks like salt to me. Water gets on top of that ledge and evaporates leaving the salt. Pic isn’t crystal clear though so I could be wrong.

Sorry, meant to address that. The picture makes it look like salt creep. It's fuzzy white mold.

Celestion · May 23, 2021

Maybe a wierd answer. mold on the paper towel will a difinitive smell

Brit’s Fish · Aug 14, 2021

Bump again! I just took the lid off my overflow box and found this mold as well. It’s definitely not salt creep. Just want to check whether it’s harmless or a sign of something wrong in my tank?