Brown Diatom Algae Takeover

[bettas_in_DE]

As the title states, I have brown diatom algae all over one of my tanks! I actually think it's starting to grow in a 2nd tank as well...

It's taken over my 5.5 g betta tank which has been running for 5 months and been cycled longer. I don't know what it would show u now, unless it's my light.

I was stupid and accidentally bought 2 of these:
https://www.amazon.com/gp/product/B07789LVNQ/?tag=ff0d01-20

I missed the part where it said Marine light, but it was growing my Ludwigia and Ammannia gracilis so well! Now they are all covered in brown algae and I have no clue what to do to get rid of it! I've tried black outs, cleaning but it doesn't come off 100%. I thought after a while it would go away on its own but it's been well over a month now!

 

[Byron]

Can you return the LED light units? They will cause you algae problems, guaranteed, because they are high in blue light but lack the red which is essential for plant photosynthesis...but algae is not so fussy.

Are you sure it is diatoms? I'm not being silly asking, I don't know how many times members have posted about brown algae as diatoms but it turns out to be a form of brush algae which can often appear dark brown. If it comes off easily with your fingertips, it is likely diatoms, but if not more certainly brush algae. Either is possible with the present lighting, but to deal with it we must pin it down.

 

[bettas_in_DE]

I asked a guy at one of my LFS about the light and he said that the blue light would be fine as it won't grow algae. Ugh. I can't return the one for the 5.5 but I can for the 10.

In the 5.5 it's definitely Diatom, but there is also what looks like green hair algae growing on the ludwigia as well.
In the 10 there is algae on the sides of the tank and some stuff that looks like spiderwebs growing on the stem plants. That is also growing on the back walls.

I borrowed an SAE from a friend but it did literally nothing. I also have nerite snails which haven't helped either. I had an ammano shrimp that didn't do anything either. I was thinking maybe Ghost Shrimp would help, but last time I got those they turned out to be Whisker Shrimp and ATE all of my fish!

10 gallon

 

[bettas_in_DE]

And then from the 5.5 gallon (they basically have the same plants!)

This tank used to be beautiful, now it's just disgusting and sad!

 

[Byron]

When any algae is "problematic," there is little that fish or snails can fix. So-called algae-eating fish will generally be very specific as to the algae species they will (or might) eat; Siamese Algae Eater will usually eat brush algae but little else. Diatoms and common green algae will be eaten by Farlowella, otocinclus and Bristlenose plecos, but even then they may not be able to handle all of it, and here there is the light issue which is only going to increase some form of "problem" algae. I never recommend acquiring any fish to deal with a problem as this often creates more problems than it solves, as the fish have requirements, behavours, traits, etc that may or may not work in each aquarium.

The light is the main issue, but there is also a nutrient deficiency. Are you using any plant additives, and if yes, which and how much/often?

The lack of red in the LED is going to result in most of the plants dying. Photosynthesis is driven by red and blue light, with red being the most important of the two. Adding green to replicate true daylight also helps plants, and it provides a true colour rendition which offsets the purplish hue of red and blue.

Water changes help with problem algae; change 50-60% of the tank volume each week, at one time (this is more effective than multiple smaller changes). Clean the open areas of substrate during the WC (this removes organics which will feed algae); obviously the organics feed plants, especially by producing the majority of CO2, but when light isn't adequate to drive photosynthesis the organics just feed algae more. Also keep the filters cleaned, the organic accumulation (the brown sludge is organics) there can promote algae too.

 

[bettas_in_DE]

I will have to clean the tanks out tomorrow then!
I honestly was to the point where I just wanted to throw all the plants out and start over!

And no I haven’t used any fertilizers or anything yet. I did order root tabs but they haven’t come in yet. I was just afraid fertilizers would make the algae worse!

What is a decent light that you would recommend then? I really don’t want to spend a ton of money on it though. So I can’t do anything like one of those Stingrays lights etc.

 

[Byron]

What is a decent light that you would recommend then? I really don’t want to spend a ton of money on it though. So I can’t do anything like one of those Stingrays lights etc.

What are Stingray lights?

I have had terrible luck with LED, tried five units, all went back. If you know what you are getting, LED is great light, but you need to know what it is and they are expensive.

I am still using T8 fluorescent. My old ballasts gave out one by one, and as I could not find new T8 fixtures I bought basic "shop lights" and used the old housing. I know this light as I have tried most of the tubes and had it since the 1980's. If you can find a T8 fixture, you will be fine. I also use CFL bulbs on my smaller tanks (10g and 20g) in the even older incandescent fixtures. Good light though.

And no I haven’t used any fertilizers or anything yet. I did order root tabs but they haven’t come in yet. I was just afraid fertilizers would make the algae worse!

Yes, when the light is not what plants need, ferts will worsen algae. But at the same time, the plants need nutrition. Substrate tabs are ideal as they feed only the plant roots, not getting into the water column, at least Seachem's Flourish Tabs are like this. Their comprehensive liquid is the one to use after the tabs, if you have floating plants, non-substrate rooted plants, or fast growing stem plants. Flourish Comprehensive Supplement is the one; forget the others in this line, not going to help.

 

[bettas_in_DE]

Stingray is an LED light from Finnex.
I have a fluorescent light on my hermit crabs that I could probably switch over for the 10 but not the 5.5, even though it's only 3000k. Maybe I will just turn the 5.5 into a SW tank seeing as I already have a light for a FOWLR tank haha.

 

[Lunar Jetman]

Apologies if I missed it above but how long are your lights on for each day?

 

[bettas_in_DE]

Around 7 hrs.

 

[Byron]

Stingray is an LED light from Finnex.
I have a fluorescent light on my hermit crabs that I could probably switch over for the 10 but not the 5.5, even though it's only 3000k. Maybe I will just turn the 5.5 into a SW tank seeing as I already have a light for a FOWLR tank haha.

From what I found online, I would not suggest Stingray LED. Reviews said insufficient for plant photosynthesis. Also, the photo shows colour diodes, white, blue and red. One unit I tried had this and the water under these was similarly coloured; it looked horrible but this is no use for plants.

If the fluorescent light is a regular tube, in T8, you can buy a better tube. One with a Kelvin of 6500K is ideal. I use this on all my single-tube and CFL bulb tanks.

 

[bettas_in_DE]

I just ended up getting a beamswork light. Not sure now the ammania gracilis will do under that light. But we will see! In the 5 some of them have green algae on them now. Luckily in the 10 it’s just that spider web stuff!

I am not sure how to clean off the live plants in the 5.5 without breaking the leaves off.