Brown algae everywhere!

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zalisfishies

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Help!
Brown ‘algae’ everywhere
I went away for a few weeks, with my tank in good condition, and since I’ve been back (2 weeks), I have not been able to get this sudden “algae” problem under control (idk if it’s algae or not).
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I have done 3 50% water changes since I’ve been back, trying to suck as much of it up as possible, and also cleaned all of the filter material & replaced the sponges. It seems like no matter how much I clean its just everywhere again right away.
I only cleaned it yesterday and it’s everywhere!?

- I have reduced the light from 10 hours to 7 hours a day, which has made not difference.
- I have not been putting any liquid fertiliser in the water when I’ve done these 3 water changes.
- Nitrate levels are at 20ppm, which is high but thats what they’ve been consistently for over a year - never had this problem before.
- 0ppm Ammonia
- 0ppm Nitrite
- 20ppm gh
- The filter is running on the strongest setting - you can see in one of the photos how many particles are in the water where the filter water is pushing them around.
- I’ve had this tank for over a year, so it’s not a cycling issue.
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Only thing I can think of is:
I’ve had consistently low ph (5.5) and 0kh for around 6 months now.. the fish all seemed happy so i havent done anything drastic to raise it - I’ve been adding some sodium bicarbonate every water change to keep it from dropping lower, but have been scared to put too much in, so it hasn’t actually raised the kh or ph levels.

My plants are all looking terrible now, presumably because of not getting enough light from being covered in this dusty algae.
Please if you have any suggestions let me know! It’s ugly af and I’m scared it’s bad for the fish with how much is in the water.

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To be honest, it looks more like loose detritus than an actual algae film. Could be dead organic matter mixed with various aquatic fungi, bacteria, etc. as well as potentially diatoms. But if it's loose particulate that can be pushed around by water flow, I'd hazard a guess that it's mostly dead organic matter. Do you gravel vac during the water changes? You could just be stirring up detritus that's sitting below your gravel. As for the sudden change: who was caring for your tank while you were gone and how were they caring for it? Often, a reason for the growth or accumulation of any organic thing is overfeeding the tank.

I don't think the low pH and KH would suddenly cause a bloom of anything, especially not if it's been at those levels consistently without issue. One thing to consider is that really strong flow from your filter might stress your fish out, depending on what species you keep. Do you only have the rasboras? Regardless, if the filter doesn't seem to be doing much to get rid of the particulate and is instead just pushing it around, I'd turn the filter back to normal or low flow, let the detritus settle, then brush it off the plants and do a very thorough, careful, deliberate gravel vac.
 
The problem with drastic acidification caused by too much decaying matter in an established tank, is that you can stall your nitrification process and promote an ammonia algae feeding bloom. When these algae die off and sink to the bottom they are eaten by bacterias that makes more ammonia.

It's a tough vicious circle. And it is very likely to appear in an rich in nutrients established tank rather than an ammonia spike.

It looks like premature "old tank syndrome" caused by overfeeding, Not enough plants to out-compete the algae of resulting nutrients.

You will have to rinse that tank a lot before it comes down. All the brown particles you are seeing are the resulting byproduct...

Even shrimps and snails don't eat that. it has to be siphoned out.

Edit: By replacing your Sponges you inadvertently redirected the food source nearly to them exclusively. It would be a plausible reason why they are doing an even stronger come back.
 
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I agree that it's detritus, what kind of filter are you running?
 
Bear in mind that there's a heavy finned betta in there too, which affects how strong the filter flow should be....
 
To be honest, it looks more like loose detritus than an actual algae film. Could be dead organic matter mixed with various aquatic fungi, bacteria, etc. as well as potentially diatoms. But if it's loose particulate that can be pushed around by water flow, I'd hazard a guess that it's mostly dead organic matter. Do you gravel vac during the water changes? You could just be stirring up detritus that's sitting below your gravel. As for the sudden change: who was caring for your tank while you were gone and how were they caring for it? Often, a reason for the growth or accumulation of any organic thing is overfeeding the tank.

I don't think the low pH and KH would suddenly cause a bloom of anything, especially not if it's been at those levels consistently without issue. One thing to consider is that really strong flow from your filter might stress your fish out, depending on what species you keep. Do you only have the rasboras? Regardless, if the filter doesn't seem to be doing much to get rid of the particulate and is instead just pushing it around, I'd turn the filter back to normal or low flow, let the detritus settle, then brush it off the plants and do a very thorough, careful, deliberate gravel vac.
Hi there, thanks so much for your detailed response!
You could absolutely be right about this - it’s something I didn’t consider but makes perfect sense. I portioned out food for my fish for my housemate to feed everyday… but when I got home he proceeded to tell me he “always added extra cos they look so happy”. So I bet you’re right on the money.
I do use a siphon when I clean the tank, but because I have soil substrate, I can’t fully press down on the substrate with it, because it sucks the soil up too much. I definitely do move it along the top of the substrate though - just without pressing down.
I do usually have my filter on the lowest flow setting - my betta swims all over the tank, sometimes sitting right where the water flows, and never seems to struggle swimming so I figured he was ok. I am actually cycling a new tank for him though as my cories have started fin nipping (not very much, but I’d rather move him anyway).
But yes I do also have the rasboras and 6 panda cories - not sure how they avoided being in any of the photos lol.
I will try the smaller, daily water changes and focus on siphoning the substrate and see how that goes!
Thanks again for your response!
 
The problem with drastic acidification caused by too much decaying matter in an established tank, is that you can stall your nitrification process and promote an ammonia algae feeding bloom. When these algae die off and sink to the bottom they are eaten by bacterias that makes more ammonia.

It's a tough vicious circle. And it is very likely to appear in an rich in nutrients established tank rather than an ammonia spike.

It looks like premature "old tank syndrome" caused by overfeeding, Not enough plants to out-compete the algae of resulting nutrients.

You will have to rinse that tank a lot before it comes down. All the brown particles you are seeing are the resulting byproduct...

Even shrimps and snails don't eat that. it has to be siphoned out.

Edit: By replacing your Sponges you inadvertently redirected the food source nearly to them exclusively. It would be a plausible reason why they are doing an even stronger come back.
Yes I did consider that the acidity could be impacting this! I just didn’t understand the science enough to actually know how.
I am planning on getting some floating plants and so more anubias to help use up some of that nitrate, since most of my plants in there are heavy root feeders and honestly probably aren’t using up much of the nitrate.
By rinsing the tank - are you referring to water changes?
And damn it! I regret removing the sponges now - I was thinking they looked a bit clogged so maybe they weren’t filtering effectively, but also I now realise I’ve removed the main source of beneficial bacteria from the tank.
I’ve got some bacteria / tank starter leftover, I will add that when I do my water changes.
 
Bear in mind that there's a heavy finned betta in there too, which affects how strong the filter flow should be....
Thankyou! I am aware, I’ve been watching him closely since turning the filter up. He seems to be behaving normally. I am going to turn the filter down now anyways though.
 
Yes I did consider that the acidity could be impacting this! I just didn’t understand the science enough to actually know how.
I am planning on getting some floating plants and so more anubias to help use up some of that nitrate, since most of my plants in there are heavy root feeders and honestly probably aren’t using up much of the nitrate.
By rinsing the tank - are you referring to water changes?
And damn it! I regret removing the sponges now - I was thinking they looked a bit clogged so maybe they weren’t filtering effectively, but also I now realise I’ve removed the main source of beneficial bacteria from the tank.
I’ve got some bacteria / tank starter leftover, I will add that when I do my water changes.

Sponges will last decades, Only need to be replaced when they start to be loose in the enclosure and water can pass beside them instead of trough.

To make sure that we are talking about the same thing: Your scape and plants becomes covered with brownish dust that is not sticking to it and can be brushed easily and will also form little balls.

Before water changes. You can stop your filter and use a turkey baster to gently blow the dust off your scape and plants towards the bottom and let it settle a bit. Start from the top of the tank and move your way down. Slowly bringing everything to the bottom.

Then try to siphon as much as you can while doing your water change.

If your filter started to smell like ammonia instead of earth. you will need to seed it regularly to get it back on track. If you have already other seasoned filters you can give it a good squeeze near the intake of the problematic tank. Adding bio-enhancer will boost your colony.

Also adding a waste control product will help convert decaying matter faster and prevent the undesirable to use it as food...

The Aquaclear Filters Have a little Hole in the bottom of the intake housing to the right. Put your Bio-enhancer directly there with a dropper so it goes trough your media before the tank.

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Btw, These sponges are 20 years old :)
 
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I agree that it's detritus, what kind of filter are you running?
I’ve got the Aquaclear hang on back filter.
Sponges will last decades, Only need to be replaced when they start to be loose in the enclosure and water can pass beside them instead of trough.

To make sure that we are talking about the same thing: Your scape and plants becomes covered with brownish dust that is not sticking to it and can be brushed easily and will also form little balls.

Before water changes. You can stop your filter and use a turkey baster to gently blow the dust off your scape and plants towards the bottom and let it settle a bit. Start from the top of the tank and move your way down. Slowly bringing everything to the bottom.

Then try to siphon as much as you can while doing your water change.

If your filter started to smell like ammonia instead of earth. you will need to seed it regularly to get it back on track. If you have already other seasoned filters you can give it a good squeeze near the intake of the problematic tank. Adding bio-enhancer will boost your colony.

Also adding a waste control product will help convert decaying matter faster and prevent the undesirable to use it as food...

The Aquaclear Filters Have a little Hole in the bottom of the intake housing to the right. Put your Bio-enhancer directly there with a dropper so it goes trough your media before the tank.

View attachment 335600

Btw, These sponges are 20 years old :)
Oh, I knew that sponges shouldn’t be replced too frequently because they hold a lot of the bacteria, but I’d thought you should replace em when they’re very visibly dirty! At least I got some use out of them by using them to help cycle my other tank before I thew them lol. Now I know, thanks!

Yes my scape and plants is covered with brownish dust. It is not stuck down and will float around the tank if I disturb the plants or move the water around. So I think it is indeed detritus and not algae.

Out of curiosity: can I increase my light back to 9/10 hours? Since it’s not algae, I figure helping the plants grow will help me with my water quality.

I will try using a turkey blaster! The last few days I’ve just used my siphon tube to swish the water around, a few minutes before siphoning the water out of the tank - but the dust just ends up settling back on the plants if I wait too long.

I use the fluval gravel vac when I do water changes. I can lightly pass over the substrate for maybe half a second in each spot, but I cant really press and hold to suck everything up because then I just suck up a bunch of soil - and shaking the soil out of the tube makes a big mess. Never knew how other people do it with the same kind of siphon I have.

Is seachem stability a bio-enhancer? That’s what I’ve been using when I do my water changes, along with prime, equilibrium and a bit of sodium bicarbonate. I just add them all into the bucket of new water that I’m adding. Is there a better way to do this?

I didn’t notice a change in scent for my tank thankfully!

Thanks so much for your help and the time you’ve put into your responses!
 
Oh, I knew that sponges shouldn’t be replced too frequently because they hold a lot of the bacteria, but I’d thought you should replace em when they’re very visibly dirty!
When sponges get dirty they should be cleaned by squeezing them in old water taken out at a water change. This applied to ceramic media as well, though obviously these noodles/balls can't be squeezed, they are just swished around in the old water.
Filter floss, the media that looks like pillow stuffing, does need to be replaced frequently as it doesn't wash properly, it goes all shapeless.
 
I use the fluval gravel vac when I do water changes. I can lightly pass over the substrate for maybe half a second in each spot, but I cant really press and hold to suck everything up because then I just suck up a bunch of soil - and shaking the soil out of the tube makes a big mess. Never knew how other people do it with the same kind of siphon I have.

Is it a planted tank type of substrate?

There are tips and tricks to using gravel vacs/syphons. If you start the syphon working, then keep your thumb over the end in the bucket, you can control the suction of the syphon. You can pause it altogether, then remove your thumb to let the water/dirt continue to flow through the syphon.

Bear in mind though, that I've only done this with gravel or sand. I haven't tried it with a planted tank substrate. But I imagine it would work in the same way, but you may lose more of your substrate than you'd really wish, but in the circumstances, if you have a decent depth, it may be worth sacrificing a little of it. I sometimes lose some of the really fine sand from my pygmy cory tank, because the sand is so fine and light, it's hard to avoid sucking up a little of it. But in that case, I can also rinse clean the sand in the bucket and replace it in the tank.

This video might seem basic when you're a more experienced hobbyist, but it's still well worth watching, because the guy in the video, Cory, has such good control over the flow of the syphon and pausing it, and even experienced hobbyists can learn some tricks from him! I learned a lot from watching him, even though he isn't right about everything, and is often promoting his businesses, but in general, he has some really good advice and tips from owning a large fish store. Both in cleaning tanks, and doing things like catching specific fish without stressing them out. Really good ways to use nets and your hand to catch fish.

Anyhow, the only real difference I'd suggest is that I find it easier to put my thumb over the bucket end of the hose when vac-ing, I find it gives me more instant control rather than crimping the hose the way Cory does in the video, but that's just a personal preference thing. Use whatever works for you.

Anyway, main point is that the syphon will pick up lighter stuff first, like the brown detritus you're trying to remove from your tank. By starting the syphon then controlling the flow using your thumb/crimping the hose, you can suction one section, then keep releasing and stopping the flow so that the lighter waste goes up the tube, but pausing it before the heavier stuff (like the sand or substrate) goes up the tube. Repeating this a few times in that one spot, before pausing the flow to move onto the next area, will give you a lot more control, and allow you to remove a lot more waste and detritus without removing too much water at once.

Without pausing the flow like that, if the syphon is constantly going, the tank will be 3/4s empty of water before you're halfway through removing the muck. But this way you'll get further.

You'll probably still need to do a lot of cleanings to remove it all, I'm sorry! But I really think this method will help you a lot. :)
 

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