Blue Green Algae?

[George2]

Hi,

   A couple months ago I introduced some plants into my 16 gallon freshwater aquarium and ever since then, I've been having trouble with some sort of algae. (Please see the attached image)

Is this  Blue Green Algae? Did this come from the plants I put in my aquarium? If I remove all plants from my aquarium, will it help the algae go away?

When I clean it up, it comes back within a day or so. This is very frustrating! I also noticed a brown algae-like substance forming on everything. It's really hard to get off the glass. Is this related? I found that if I reduce my light, the brown stuff takes longer to form.

My water quality is:
Ammonia: 0
Nitrites: 0
Nitrates: ~5ppm
PH Level: 7.4
Temperature: 77-78
feeding: I feed the fish once per day.


I have been doing 30%-40% water changes at least once or twice a week.

I read the following:
http://www.theplantedtank.co.uk/algae.htm
from a previous post and it says to cover up my aquarium for 3-4 days so no light gets in. This seems drastic. I have pencil fish and ember tetras. Can they go that long without eating? Will this impact my bacteria cycle in my aquarium?


Thanks!
George

[blueknight0303]

the plants and fish can go on without lights for a week. you can turn on the lights for a few mins when feeding time. make sure you are not overfeeding. blue green algae is a bacteria that needs light to photosynthesize so they will not go away as long as there are lights in the tank. mine disappeared after 2 weeks of total blackout and turning the lights on for 2-5 mins during feeding time.

[exv152]

That's blue green algae, but like the algae guides suggests, it's most likely caused by low nitrates which is reflected in your test results. You want the nitrates to be a bit higher closer to 20ppm, and the addition of the plants didn't introduce the algae. Also pencil fish and embers are a very low bio load, you might want to consider adding more fish and/or supplimenting some KNO3 to get rid of the algae. I think you have too little algae to warrant a blackout. I would leave that for a serious case of BGA which you don't have. You can also trying siphoning it out with your next WC.

[George2]

the plants and fish can go on without lights for a week. you can turn on the lights for a few mins when feeding time. make sure you are not overfeeding. blue green algae is a bacteria that needs light to photosynthesize so they will not go away as long as there are lights in the tank. mine disappeared after 2 weeks of total blackout and turning the lights on for 2-5 mins during feeding time.

Once you got rid of it, did it ever come back again? i.e. can it be permanently eradicated?

[George2]

That's blue green algae, but like the algae guides suggests, it's most likely caused by low nitrates which is reflected in your test results. You want the nitrates to be a bit higher closer to 20ppm, and the addition of the plants didn't introduce the algae. Also pencil fish and embers are a very low bio load, you might want to consider adding more fish and/or supplimenting some KNO3 to get rid of the algae. I think you have too little algae to warrant a blackout. I would leave that for a serious case of BGA which you don't have. You can also trying siphoning it out with your next WC.

Right now I have 10 ember tetras and 4 pencilfish in my 16 gallon tank. Do you think I can/should add more fish?

I have been doing alot of water changes (twice a week) to try and get rid of the algae. Is that making it worse? Should I ease off on the water changes?

[exv152]

Right now I have 10 ember tetras and 4 pencilfish in my 16 gallon tank. Do you think I can/should add more fish?

I have been doing alot of water changes (twice a week) to try and get rid of the algae. Is that making it worse? Should I ease off on the water changes?

I'm not sure how old your setup is. If it's fairly new I wouldn't add more fish just yet. Only one of the reasons listed is low nitrates, the others are ammonia and poor water circulation. You didn't say whether or not you're fertilizing your plants, but if you're not, doing 40% WCs twice a week is going to strip your tank of several essential nutrients plants need. I also assume you're not adding any CO2, and you have low light intensity?

[blueknight0303]

Once you got rid of it, did it ever come back again? i.e. can it be permanently eradicated?

it did not come back. in your case, try a week. algae eating snails or fish wouldn't touch them because they are not really an "algae" but "bacteria". make sure you estimate your feeding properly because if you are having BGA then you are bound to have Green Algae and black brush algae soon.

[blueknight0303]

I'm not sure how old your setup is. If it's fairly new I wouldn't add more fish just yet. Only one of the reasons listed is low nitrates, the others are ammonia and poor water circulation. You didn't say whether or not you're fertilizing your plants, but if you're not, doing 40% WCs twice a week is going to strip your tank of several essential nutrients plants need. I also assume you're not adding any CO2, and you have low light intensity?

he is also right. poor water circulation is a huge factor too.

[George2]

I'm not sure how old your setup is. If it's fairly new I wouldn't add more fish just yet. Only one of the reasons listed is low nitrates, the others are ammonia and poor water circulation. You didn't say whether or not you're fertilizing your plants, but if you're not, doing 40% WCs twice a week is going to strip your tank of several essential nutrients plants need. I also assume you're not adding any CO2, and you have low light intensity?

I guess I need to increase the nitrates. Is that harmful to the fish, though? If I overfeed my fish, will that increase the nitrates?

If I don't do a water change for more than a few days, the algae seems to really explode. What I've been doing is rubbing off the algae from the substrate and then sucking it up when I do the water change. I'll reduce my water changes and see what happens.

Originally I used a T5 HO light, but that seemed to create an explosion of brown algae (I think it is a diatom?). Within a few days, everything was brown, including the plants. Therefore, I put back my lower intensity light. After I did this, the brown algae immediately slowed down to the point where it is now just a nuisance instead of a big problem.

I have never used any CO2. I did put some Nutrient Tabs under some of the plants a couple months ago, but that is about it for fertilizer. Will extra fertilizer trigger the Blue Green Algae to grow faster?

[George2]

he is also right. poor water circulation is a huge factor too.

I assume my water circulation is ok. I am using a an AquaClear 20, which is good for tanks up to 20 gallons, on my 16 gallon tank.  When the fish swim across the filter, I can see them being pushed down by the filter current. Does this sound like I have sufficent water circulation?

BY the way, I have a 16 gallon tank, which is tall. (20L x 10W x 18H) Perhaps the water movement is not making it all the way to the bottom?

[exv152]

If you've tried the heavy water change approach and it's still not going away then I would definitely be suspicious it's related to a low nutrient deficiency ie; nitrates. Look into KNO3 or potassium nitrate in dry form, and it's safe for fish, many of us use it in high tech setups and dose it up to three times a week, without any ill effects. I would also look into a general purpose liquid fertilizer like seachem flourish comprehensive and add a dose every week. That should help replenish some of the micro nutrients. Down the road I would also increase the filtration.

[robt18]

BGA, which is cyanobacteria, as previously pointed out, in my experience hasn't responded well to traditional algae eradication methods. The best way to kill it off is erythromycin, an anti-bacterial medication. It isn't that hard on fish (not in my experience at least), and I have found it is the best chance at permanently removing it from your tank.

[George2]

If you've tried the heavy water change approach and it's still not going away then I would definitely be suspicious it's related to a low nutrient deficiency ie; nitrates. Look into KNO3 or potassium nitrate in dry form, and it's safe for fish, many of us use it in high tech setups and dose it up to three times a week, without any ill effects. I would also look into a general purpose liquid fertilizer like seachem flourish comprehensive and add a dose every week. That should help replenish some of the micro nutrients. Down the road I would also increase the filtration.

I think you're right about the nitrates. I was always under the assumption that too many nitrates are a bad thing. I'll try adding fertilizer and see if that helps. If I increase the amount I feed my fish, will that also increase the nitrate levels?

[George2]

BGA, which is cyanobacteria, as previously pointed out, in my experience hasn't responded well to traditional algae eradication methods. The best way to kill it off is erythromycin, an anti-bacterial medication. It isn't that hard on fish (not in my experience at least), and I have found it is the best chance at permanently removing it from your tank.

Does the erythromycin have any impact on the good bacteria in my aquarium? i.e. will it impact the ammonia->nitrite->nitrate cycle? If I don't have any luck when I add extra fertilizer, I'll pick up some erythromycin.

[blueknight0303]

BGA's attitutude is stay on an area with low current and absorb light and nutrients. try  adding an airstone or total blackout for a week. i wouldnt recommend using meds right away.

[robt18]

Does the erythromycin have any impact on the good bacteria in my aquarium? i.e. will it impact the ammonia->nitrite->nitrate cycle? If I don't have any luck when I add extra fertilizer, I'll pick up some erythromycin.

It will kill off some of your good bacteria as well, feed less during/immediately after the treatment. The bacteria will of course be built up over the course of a few weeks after.

[exv152]

I think you're right about the nitrates. I was always under the assumption that too many nitrates are a bad thing. I'll try adding fertilizer and see if that helps. If I increase the amount I feed my fish, will that also increase the nitrate levels?

Yeah, you want to get to the root of the cause and fix it there, as opposed to putting band aid solutions on the problem. I would not overfeed the fish, that'll just pollute the tank. But adding nitrates and reducing the WCs to say 20% a week is a good start. And testing for nitrates as you go.

[Montrealguy]

I would never use erythromicin, as antibiotics are too precious to be wasted on aquarium decor. I get occasional outbreaks of Cyanobacter, and a week with no lights does the trick. If it returns, then another week.
I see it when I have wisteria - H diformis - in the tank. I know that's weird, but there's a connection in my water. It does better in low planting, high fishload tanks  - I see it mainly in fry tanks. It's easy to eradicate, and to keep away. To a degree, it feeds on water changes, but only to a point. Aggressive water changing routines after the light starvation seem to finish it off for me.
It always returns eventually, but that can be a matter of years.

[George2]

Thanks everyone for all of the great suggestions and advice.   

[Harris625]

Some types of algae looks good but green algae is dangerous in aquarium. It can be overcome by proper filtration and LED lighting.