5 Gallon Tank Weird black thread algae??

[justinfinderlake]

I’ve had a new 5 gallon tank for like 3 ish months now and in the last couple of weeks I’ve noticed these weird sections of like black strings coming from things?? It was only on a piece of my driftwood at first but I just got home and now it’s spread to one of my plants to. I just have no idea what it is?? I have a bunch of snails, white cloud minnows, and like 3 amano shrimp in this tank and the only thing I’ve been adding recently was some fertilizer for the plants like every other week. Is there any way to fix it? I’ve done the water tests strips and everything is in perfect ranges.

Oh and also it looks like the leaves in the bottom of my pink plants are like degrading?? But every other plant is doing super good

 

[Fishfur]

I’ve had a new 5 gallon tank for like 3 ish months now and in the last couple of weeks I’ve noticed these weird sections of like black strings coming from things?? It was only on a piece of my driftwood at first but I just got home and now it’s spread to one of my plants to. I just have no idea what it is?? I have a bunch of snails, white cloud minnows, and like 3 amano shrimp in this tank and the only thing I’ve been adding recently was some fertilizer for the plants like every other week. Is there any way to fix it? I’ve done the water tests strips and everything is in perfect ranges.

Oh and also it looks like the leaves in the bottom of my pink plants are like degrading?? But every other plant is doing super good

There is likely too intense lighting or too many hours of lighting. The black threads sound like red algae.

What’s the water temperature?

Those bottom leaves look to have algae growing on them so they should be removed immediately.

 

[justinfinderlake]

There is likely too intense lighting or too many hours of lighting. The black threads sound like red algae.

What’s the water temperature?

Those bottom leaves look to have algae growing on them so they should be removed immediately.

There’s no heater in it so it ranges from around 62 to 65 depending on the day, and I will def remove some of the bottom leaves. I usually keep the light on about 8 hours a day but I will lower the time it’s on

 

[3Fishnight]

Staghorn algae
https://greenaqua.hu/en/alga-tajeko...iWjd8ppQ9PJjfL2n27UCBq5d-lIy48ZTEepSbavlndVsL

 

[Fishfur]

There’s no heater in it so it ranges from around 62 to 65 depending on the day, and I will def remove some of the bottom leaves. I usually keep the light on about 8 hours a day but I will lower the time it’s on

If the light is too intense, now that algae has started growing, simply reducing the hours isn’t going to be enough to clean up the problem.

What fixture do you have and is it dimmable?

 

[justinfinderlake]

If the light is too intense, now that algae has started growing, simply reducing the hours isn’t going to be enough to clean up the problem.

What fixture do you have and is it dimmable?

I’m not sure because it came in like a starter set I’m pretty sure it’s top-fin and I know it’s 6500k but it’s not dimmable, another person said it was staghorn algae and it looks like it is

Staghorn algae
The Ultimate Algae Guide

That actually looks pretty identical, any tips on how to fix it? I’ve just cut off the leaves with it but not really sure how to do the parts where it is on the wood I’ve heard hydrogen peroxide might work?

 

[Fishfur]

I’m not sure because it came in like a starter set I’m pretty sure it’s top-fin and I know it’s 6500k but it’s not dimmable, another person said it was staghorn algae and it looks like it is


That actually looks pretty identical, any tips on how to fix it? I’ve just cut off the leaves with it but not really sure how to do the parts where it is on the wood I’ve heard hydrogen peroxide might work?

Can you raise the light higher ?

The trick to stopping algae is to amend whatever triggered it in the first place, then clean it out if the tank.

Anything that can be removed to be scrubbed or bleached or soaked in H2O2 should be removed and cleaned.

I would run a spare HOB filter if possible, stuffed with floss only, and temporarily turn off the regular filter before starting the cleanup.

Or remove the filter media from the filter temporarily & replace it with floss.

Floss will catch all the loose bits of algae that are going to escape you. Once cleanup is done, let the floss filled filter run for a few hours to make sure it catches everything.

Then toss the floss with all the algae bits it caught.

Scrape algae off glass or other surfaces, filter parts, airstones, whatever its growing on.

Any plant leaves with algae should be removed & tossed. This might mean snipping bare stems off & replanting the clean remainder.

Unless there are only a few tiny spots with algae, spot treating is too time consuming & tedious. I think k it’s best to tackle it all at once and then hopefully it’s done and won’t reoccur, assuming that whatever triggered it in the first place has been remedied.

You might find this article of some use.

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A few things to know about algae

Feb 4, 2025

Numerous sites consulted for biological details

• Fishfur
• Freshwater Aquarium Articles