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Cyanobacteria in the freshwater planted aquarium

24K views 103 replies 11 participants last post by  xfatdannx 
#1 ·
Hello Byron and everyone else,
I was wondering if you could share a bit of wisdom. I have read on some of your posts that circulating pumps in a planted tank were not really beneficial and may actually do more harm than good by depleting co2. I have a planted 55 gal. Aquarium with sand substrate on top and Eco complete and other dirt underneath. In my previous tank which was all dirt I was having the same issue until I installed a circulating pump after which it cleared it right up. I'm changing 30 percent of my water once a week and when I do, I suck up the green stuff but by the next week when it's time to do a water change it comes back. My parameters are 76 deg, ph of 7.5 nitrate 10 ppm ammonia 0 nitrite 0. Any tips would be greatly appreciated. I'm using Rena xp2 filtration, 2 24 inch coralife light fixtures with 4 6700 k t5 bulbs 14 watts
each. I went ahead and placed a circulating pump in my tank but don't really like it. I don't over feed, so was just wondering if adding more plants would get rid of this problem. In other words, being a heavily planted tank I would assume that there are dead spots at the bottom of the tank. My tank is planted, but not that heavily at the moment. Sorry Byron about posting in the wrong place. Kind of a lengthy question, but any tips would be greatly appreciated.



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#2 ·
having a algae issue or just a cyano problem? x8 tubes if i understand right is wayyyyyyyyy to much light without any co2 injection and low plants. that just breeds problems and imbalance. with that much light add some more plants and co2 to see a cutback of the algae and cyano. or cut back atelast half of that light untill you get some co2.
 
#3 ·
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#6 ·
I think the root cause of cyanobacteria is more excess 'nutrients' than light. Do you have high nitrates and/or phosphorus in the tank? Lowering these, in addition or in conjunction to increased volume/frequency of water changes, may resolve the problem.
 
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#7 ·
True, if CB is what it is.

With the really light coloured sand I might wonder if it's just a little mulm showing up. Increasing circulation would serve to not let this settle and it would get sucked up in the filter.

My tank has higher circulation than I intended so it doesn't even get any kind of buildup on the bottom, I try to vacuum the sand and my pail has practically nothing to show for it... even when I let it go for two weeks.

Jeff.
 
#8 ·
Cyanobacteria is caused by excess organics. Without organics, cyano is not going to appear, regardless of light, water flow, etc. I have 7 tanks running, four of which have very little water movement as they are filtered with a single sponge filter, and they range from 10g, 20g, 29g and a 3-foot 33g. If minimal or low water movement were responsible, these tanks would be covered in cyano.

I have had cyano in one tank, twice. This was my former 70g setup, which had a canister filter the same as it does now, and the same as my 90g and 115g. Again, water movement has nothing to do with cyano. Nor does light, though too much light, in the presence of organics, can trigger it. And too few water changes, overstocking, over-feeding...these can contribute too.

To make sure I understand things correctly, mikey: the light is 4 24-inch T5 NO tubes, you have CO2 diffusion, and a partial soil/Eco-complete substrate. How long is the light period daily? And I assume the CO2 is not left running during darkness (= tank lights off)?

Also, could you post a photo, just in case this is not cyano but is more normal as another member suggested. And a photo of the tank to see the plant level would help.

Byron.
 
#9 ·
I do 30 percent water changes once a week. I usually run my lights for 9.5 hours. As far as feeding, I feed my fish once a day and they generally eat just about everything in 5 minutes. What little does happen to fall to the bottom I have two Amanos that take care of that. I've attached a picture of my tank, but just did a water change last night, so I just got rid of all the green slime that was accumulating.

my Tank. - 55 gallon Freshwater fish tank


 
#11 ·



This is an image of cyanobacteria in my local Petco tank. Its why I don't buy plants or fish from them. Its normally greener bit its the greenish brown stuff on the base of the plant and on the gravel. When you touch it it free floats in a sheet. I had it in my 10 gallon because i had 6 white cloud mountain minnows and their 27 babies in the tank. While I did good water changes the hikari baby fish powder was also partially to blame. I did a whole box of EM and kept up on water changes as directed on box and it cleared up
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#12 ·
Try killing the lights and suspending feeding until the cyano dies off.

Then resume with less lighting (duration) and feeding and adjust until the plants thrive but not the cyano/algae.


my .02
 
#13 ·
Mikey, is what you had the same as what is showing in the photo Aurie posted? Because that is cyanobacteria. It is slimy, easily comes off with your fingers, will stain your fingers and anything else green, etc. In my tank is was much brighter green, but cyano can be red, green, almost black, or anything between.

You will have better results when the plants are fuller; right now they are minimal so not doing a lot with respect to nutrients/organics.

And here I must mention the soil. This is usually a high source of organics, depending upon where it came from. It would not surprise me at all if the cyano is due to the soil leeching organics into the water. Not suggesting pulling it out, but only pointing out this likely source. Again, more plants or increased plant growth should help.

I would reduce the light duration down to 8 hours daily. I would also increase the water changes to at least half the tank volume once weekly. The issue with both suggestions is to limit the light and organics to prevent cyano from taking hold. There has to be a balance, and clearly this is not occurring (assuming cyano is the issue).

Byron.
 
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#14 ·
YES, thank you Byron I think you've helped me figure it out. I also believe that my culprit is the soil under the sand, I mixed my Eco complete with this expensive supposedly real fertile volcanic soil I bought at my LFS. I think it's a little too fertile LoL. I was really noticing the cyano at the base of some of my plants. It is a light green color like in the picture and where it was more concentrated it was a bit darker and slimy looking. Stinks too. I could smell it when I had removed it to my bucket.
So thank you soo much for your help and everyone else who has been trying to help me. I will try what you said and remove more water, add a bit more plants and let the ones I already have get abit bigger. Thank you!
 
#15 ·
Also - Cyano makes your tank STINK like a swamp. I did my water change and OMG my roomate had to leave the room as I dumped the water outside my living room door (for my rose bushes) .. When your tank stinks worse than PRIME then you know you have a problem LOL.. ok it's not a laughing matter, but it was in my case. I gassed out my roomate without even farting hehe
 
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#17 ·
I am having the same issue but i think mine was induced by light. I was having minimal algae problems before, but i went out of town with my band for the weekend on the 15th and 16th. Came back to discover i left the timer on "on" not "timer". I had turned the lights on early Friday before leaving trying to make sure everything would be okay while i was gone and i just made it all worse.

So i am feeding daily with hardly any food making it to the bottom. Water changes are either every day to every other day depending on how much "slime" accumulates. With it just run its course eventually? Should i remove plants and clean them as the slime does not just slide right off them or the lava rock? Thanks in advance.
 
#18 ·
I am having the same issue but i think mine was induced by light. I was having minimal algae problems before, but i went out of town with my band for the weekend on the 15th and 16th. Came back to discover i left the timer on "on" not "timer". I had turned the lights on early Friday before leaving trying to make sure everything would be okay while i was gone and i just made it all worse.

So i am feeding daily with hardly any food making it to the bottom. Water changes are either every day to every other day depending on how much "slime" accumulates. With it just run its course eventually? Should i remove plants and clean them as the slime does not just slide right off them or the lava rock? Thanks in advance.

I would not remove live plants.

As stated before just kill the light and suspend feedings. The cyano will die off providing nutrients for the plants. So you rebalance the tank. The resuming your original lighting will help assure the cyano stays away and the plant thrive.


my .02
 
#20 ·
As I have said previously here and in other threads, cyanobacteria is caused by high organics. Obviously light has to be present. But without reducing organics you will not be able to remove cyano.

If I read your post correctly, the light was left on for several days. Cyano is the least of your worries. Light 24/7 is highly stressful on fish, as it deprives them of the needed period of complete darkness. You can read more here if interested:
http://www.tropicalfishkeeping.com/freshwater-articles/lighting-how-affects-freshwater-fish-81982/

It is very common for fish to come down with ich (white spot) under such circumstances, so keep a very close eye out. Ich is caused by stress, and in this case stress occurs due to the continual light.

Back to the cyano. Do water changes, vacuum the substrate, remove as much as you can with your fingers (prior to the water change, as it falls to the substrate and can be siphoned off). Feed sparingly. Don't add plant fertilizers for a couple weeks.

Byron.
 
#21 ·
This cleaning process was in part to remove fertilizer, as i had osmocote in the substrate (and will no longer be using it). This was added AFTER the "slime" started showing up. After the water change, Nitrates were lowered, and fish stress levels were obviously lowering as more natural colors were starting to return. Will keep an eye out for ich.

I think the light started the cyano, and then adding the ferts just fed it as my nitrates were at about 60ppm a day or two after adding ferts.
 
#23 ·
I'm pretty sure that nitrogen off gases quickly from water, more so than CO2, so I doubt that it would be much of a factor in feeding a nitrogen fixer. Someone with some working knowledge of partial pressures would be able to better answer that though, I'd have to refresh my memory on that one.

Jeff.
 
#24 ·
Hello:
is it possible that atmosphere nitrogen dissolves in water and maybe pressure is related to how fast organic nitrogen is dissolved and saturation levels reached. Organic nitrogen may be important to the micro ecology of the water column. By gassing out do you mean evaporation into the atmosphere?

NOTE: POP’S OPINION IS NOT ASSOCIATED WITH ANY FACT OR RESEARCH, IF THERE IS ANY RELATIONSHIP WITH A KNOWN FACT OR TRUTH OR SCIENCE THAT RELATIONSHIP IS ACCIDENTAL.

pop
 
#25 ·
NOTE: POP’S OPINION IS NOT ASSOCIATED WITH ANY FACT OR RESEARCH, IF THERE IS ANY RELATIONSHIP WITH A KNOWN FACT OR TRUTH OR SCIENCE THAT RELATIONSHIP IS ACCIDENTAL.

pop
So what you are saying is that this is purely fictional...:roll:

is it possible that atmosphere nitrogen dissolves in water and maybe pressure is related to how fast organic nitrogen is dissolved and saturation levels reached. Organic nitrogen may be important to the micro ecology of the water column. By gassing out do you mean evaporation into the atmosphere?
It does dissolve in water to somewhere around 20ppm at 1 atmosphere at around room temperature.

Ammonia, nitrite and nitrate are far more readily dissolved in water so the N2 will not affect their respective concentrations in any easily measurable way. Seeing as air is always about 78% N2 this is a constant factor and not something that we can change and even if we bumped it up to 100% the water will not absorb much more than the atmospheric air baseline.

By off gassing I am suggesting that the concentration of N2 dissolved in the water will not increase past the approximate 20ppm level from the air. If there is a source of N2 from within the tank it will form micro bubbles of undissolved gas and escape to the surface. This is what happens when divers get the "bends" as the nitrogen gas comes out of solution in the blood stream and cannot be off gassed fast enough through respiration. It only builds up due to the increased pressure under the water. As the air is breathed (with it's 78% N2 content) it diffuses into the blood. At depth, say 90 feet, the pressure is equivalent to 4 atmospheres (this affects the air breathed by compressing it) which means that there is just more N2 per breath which will dissolve into the blood that much more readily due to the pressure.

NH3 concentration can be as high as 500,000ppm (yes that is the same as half of the water being ammonia) but this cannot happen in a natural setting as there would never be that much ammonia to be dissolved in the water. The point being that ammonia is so readily dissolved that a little N2 won't affect it.

For reference, CO2 can be as high as 1,500ppm, but again, this is not possible as a 100% pure CO2 atmosphere would be needed to do this.

There are some charts that reference gas solubility in water at this link. I knew the reasoning but didn't realize the numbers would be so large for CO2 and NH3.

Sorry, no proof reading time this time.

Jeff.
 
#26 ·
Hello JDM:
The possibility of what I think or may say being fiction is acceptable notion as far as I am concerned.…… I take great joy in distorting facts and truths by omission and speculation. Have you ever left out an aspect of a truth just to make your story better? I have.

I like what you said about the bends and the build up of nitrogen in body fluids. Can this happen to fish as well? can fish have nitrogen bubbles in their blood and other fluids. If this is the case then can nitrogen build up in body fluids have an effect on the osmoregulation process or respiration.

Its been fun
pop
 
#27 ·
I think we've sidetracked this thread Pop.

I may omit certain facts under certain circumstances but not when it comes to arguments that rely on factual representation. If the facts that I know lead me to a different conclusion due to a differing point of view or conflict with some one else's facts, I'd prefer to have it all out on the table rather than having to backtrack and reveal "hidden" facts.

Fish don't breath air, and the water has a very low N2 content so they cannot have it build up in their blood. On the other hand fish can have a "barotrauma" if they are taken from depth quickly, their swim bladders can rupture due to the same laws that cause the nitrogen to be able to bend a diver. Death from being bent is due to the nitrogen bubbles entering the heart and other damage can be caused in the sub dermal layers, muscles, lungs and other areas of good blood flow as the bubbles are captured in various veins.

Anyway. I think that wraps that topic at least in this thread.

Jeff.
 
#28 ·
Getting back to the issue of cyanobacteria, it is true that nitrogen is involved. For those wanting a brief summary, this site (UC at Berkley) has one:
Life History and Ecology of Cyanobacteria

Some aquarists advocate increasing nitrate to combat cyanobacteria, holding that it occurs when nitrate is very low. There are two problems with this. First, I and many others have tanks with near-zero nitrate and never see cyanobacteria in these. Second, and much more important, is the fact that nitrates do affect fish. There is no sense in putting fish at risk just to deal with cyanobacteria when it can be eliminated more safely.

Byron.
 
#29 ·
@Byron - I am doing about 20-30% water changes a day to try and keep my Nitrates down. As stated previously, they spiked after i added ferts. Also as stated the cleaning out of my take was to remove ferts from substrate. Now, you say the cyano feeds off the phosphate? Is that correct? Should that be the next thing i look at testing/removing from my tank? Or should i be adding more plant? (Such as anacharis that gross SUPER fast)? Thanks for your help. I am checking out your other link now.
 
#30 ·
I know nothing of the link (if there is one) between phosphates and cyano. Cyano is organics-related. Unless you have high phosphates in your source water, this is not likely to be an issue.
 
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