Diatom Nightmare! Light or no light

So I clearly have a diatom issue! I’ve read so many things however I’m even more confused than when I started as all the information I’ve read is conflicting! My parameters are great ph 7.5 ammonia 0 nitrite zero and nitrates 12.5mg.
it’s a newly cycled tank so I know this is normal. However it looks filthy! It’s so disheartening! It’s been going on over a week now. If my partner moans at me one more time about how filthy the tank is and it shouldn’t look like that one more time he’s going in the tank with the fish. So my question is how do I get on top of this? I’m doing my weekly 50% water changes and I have reduced feeding to a tiny pinch once a day. I even skipped a day a few days ago when it looked really bad, do I need to do more water changes? Should I turn my filter off when doing the water change? Should I rinse off my ornaments, rocks, wipe both my artificial and real plants. How long should I have my light on if it at all. Is there anything I should add to my water? Any general hints and tips. So disheartened right now, just some reassurance that this will go away would be great. Tips on how to shut up my partner would help too lol!!! He knows nothing at all about aquariums even less than me other than my water should be crystal clear ?

Diatoms can be easily removed.
Just wipe them off with a piece of sponge, cloth or even paper towel.

What is your lighting wattage and how big is your tank?
Reduce your light brightness.

What kind of substrate is in the tank?

the guy at my local fish store told me to get some snails and they would eat the diatoms. I did, got 2 nerite snails and 2 mystery snails. Tank has been clean ever since.

Diatoms are typical in a cycling aquarium. It’s probably the high nitrates, as diatoms love to eat nitrates. (You put it in mg. Do you know what the ppm reading is for the nitrates?)

Diatoms are fairly easy to remove. I suggest you perform a large water change, scrub the glass/decor, and perform a substrate vacuum. The easiest way to remove it is to do it all manually.

This is the thread I used for reference, when I had diatoms: https://modestfish.com/brown-algae/

Hi all thank you for your replies. I currently have Hugo kamishi black glass decorative substrate.

I have the Juwel Vision 180 led with internal lights in the hood which unfortunately don’t dim. Specs are below copied from the Juwel website. I did order a blue light in place of the day bulb and ran that for a couple of weeks whilst cycling. As I felt it was too bright and didn’t understand the importance of correct lighting. I’ve swapped the blue back out and put the day bulb back in. I only have two Java plants marisimo balls and some duckweed in there along with artificial plants. The Java plants have nearly doubled in size since I got them a couple of weeks ago.


Brilliant luminosity and excellent plant growth are what you get with the state-of-the-art Multilux LED lighting technology from Juwel. The replaceable 19w Day and Nature LED tubes create an optimum light spectrum, while saving up to 50% of energy in comparison to T5 at the same time. The MultiLux LED lighting system for the Vision 180 LED means that you can work on your aquarium in comfort, even when the lighting is switched on.

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With regards to nitrates I wouldn’t know how to tell you that in ppm I’m just reading from my tetra testing kit. Which shows 12.5mg/l However when testing my tap water I get the same result. It’s not faulty as whilst I was going through the cycle I was showing the next level up.

I do intent to add some more plants and stripping the tank of the ornaments and adding rocks and wood. I’m just dubious as I have no soil etc in the tank & wouldn’t even know how to begin with moving the fish whilst I changed it all.

When doing water changes should I turn off the filter to stop the buggers moving around? Also do you think my filteration is adequate. I’m running the fluval 207 canister. I do still have the original Juwel 600 eco pump internal filter that came with the tank I took it out as it took up a big chunk of space. So I could re-add it if it would help & run both. Im
Also running 2 air stones.

looking at the photos it’s starting to look more green than brown? Is that a positive. However the stuff on the glass ornaments etc is definitely brown and powdery.

Black glass, or black quartz? I only see the black quartz on the website...at any rate, if that substrate is full of silicates, you'll be dealing with diatoms (brown "algae") for a very long time, unfortunately

I found out the hard way, with black Tahitian Moon sand...

R84achey said:

Which shows 12.5mg/l

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That’s interesting... Is that a strip or liquid test kit?

PheonixKingZ said:

That’s interesting... Is that a strip or liquid test kit?

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They are liquid test kits. Got swindled by lfs as it’s cost me £50 for an ammonia test kit, ph, nitrite & nitrate. I’ve literally just run out as well so I’ve ordered the API liquid test kit.

Slaphppy7 said:

Black glass, or black quartz? I only see the black quartz on the website...at any rate, if that substrate is full of silicates, you'll be dealing with diatoms (brown "algae") for a very long time, unfortunately

I found out the hard way, with black Tahitian Moon sand...

Sands | Hugo Kamishi

hugokamishi.com

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I’m not sure it’s literally called black glass. Why would they bloody sell it if it’s going to mess up my aquarium ? kicking myself as I should of got sand but wanted something black

R84achey said:

I’m not sure it’s literally called black glass. Why would they bloody sell it if it’s going to mess up my aquarium ? kicking myself as I should of got sand but wanted something black

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That’s the description. I’d read that gravel glass etc can’t leak silicates unless your hundreds of metres under the sea. However silicate sand does. This is what I mean though there’s so many contradicting posts. Any advice regarding lights. Do you think it’s advisable to take out the ornaments as heard they can add silicates to the water? Honestly if I knew what I was doing I’d strip it all down and start again. Could I move my water and filter into another tank temporarily with the fish whilst I redo the tank and get it planted etc?

PheonixKingZ said:

Diatoms are typical in a cycling aquarium. It’s probably the high nitrates, as diatoms love to eat nitrates. (You put it in mg. Do you know what the ppm reading is for the nitrates?)

Diatoms are fairly easy to remove. I suggest you perform a large water change, scrub the glass/decor, and perform a substrate vacuum. The easiest way to remove it is to do it all manually.

This is the thread I used for reference, when I had diatoms: https://modestfish.com/brown-algae/

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Just checked and the mg/l is just the same as ppm so 12.5ppm. I’m not concerned with that as my tap water is the same

Yes, mg/l and ppm are so close that they are interchangeable.

R84achey said:

Just checked and the mg/l is just the same as ppm so 12.5ppm. I’m not concerned with that as my tap water is the same

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12.5ppm of nitrate really isn’t that much. It’s generally recommended to keep it below 10ppm.

Those “diatoms” really look more green than brown.

@mbsqw1d, any ideas?

PheonixKingZ said:

12.5ppm of nitrate really isn’t that much. It’s generally recommended to keep it below 10ppm.

Those “diatoms” really look more green than brown.

@mbsqw1d, any ideas?

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It is starting to look more green, however when I wipe it away it is a rusty brown colour and powdery xx