blue-green algae outbreak + listing water params

[resk]

37g tank (32g volume)
2x65w powercompact

ph: 6.8
dkh: 6
co2: 29ppm

no3: between 5.0 and 10.0 (kit is crappy)
po4: between .5 and 1.0 (again, crap)

P is dosed - 1/2 teaspoon of potassium sulfate (20ppm roughly)
once a week

traces - teaspoon of kent 'freshwater plant' once a week

root ferts - used 'dupla root' for 30g

50% water changes every other day

OK..

pics of my blue-algae outbreak are attached.

This outbreak keeps persisting, and has been going for about 2 weeks.

what should I do ?

[Richer]

How often is pottassium dosed? Do you dose traces?

I slacked off a little while ago during my finals and as a reward I had a particularly nasty cyano (aka. blue-green algae) outbreak. I tried fixing it by doing a 50% water change, then a 4 day blackout. After that, another 50% water change, and starting dosing my fertillizers properly again... however, that didn't fix the problem. What went wrong? I forgot to dose my traces :rolleyes:. Soon as I dosed my traces, all the bga in my tank vanished.

HTH
-Richer

[resk]

i edited the original post to include that info.

i think you are right about the traces

kent directions say to use 5-15ml 1 to 3 times a week "depending on the number of plants"

ive got my 37g (high) virtually full of stem plants, the bunch plants and little grasses have had a hard time getting established due to the adverse algae growths

this blue-green algae is much easier to remove than some of the other stuff ive had to mess with

thanks !

[resk]

ive been dosing the traces at the recommended level for the last 2 water changes...

overnight the blue-green sheet on the glass is still growing

i performed a 50% yesterday, and got home today and still had another outbreak

i don't know what is going on, maybe this isn't blue-green algae ?

the stuff just comes right off the glass, and makes a cloud in the water, then i fill the tank and the bottom half of the tank's glass is caked with the residue

this is annoying, what else should i check besides the above mentioned ?

[Richer]

Remove as much as you can by hand. Clean out your mechanical filters and do a 50% water change. Add airstones, and raise spray bars if you have any... anything to increase surface aggitation. Cover your tank with heavy blankets, or black garbage bags... or something that will prevent light from getting into the tank. Leave the tanks lights off. Keep the tank running like this for about 4 days, meanwhile, don't feed your fish (they'll be just fine) and make sure no light can get into the tank. Afterwards, remove the cover, clean out your mechanical filters again, and do another 50% water change. Then dose your tank with the proper amount of fertillizer.

Keep in mind that the "proper" amount of fertillizer in a CO2 + high light supplemented tank is different than that stated on a fertillizer bottle. For example, I dose 3-4 capful of Seachem Flourish every 3 days (thats about 20ml at a time) on my 70 gallon tank. Much more than what is recommended on the bottle. You can also try increasing water flow over certain areas of your tank. There was a stubborn bga on some anubias I had, I just added a powerhead and directed water flow over that area. The BGA here has long since vanished, and I've removed the powerhead.

HTH
-Richer

[resk]

i can't wait to have my tank back

[plantbrain]

In addition to what's been said, I typically do the 3 day blackout routine to kill the BGA.

But I also add KNO3, about 1/3 teaspoon 2-3x a week is what you will be adding unless you have a heavy fish load which I doubt given the algae in question.

So do this:
50% weekly water change
Keep the CO2 at 20-30ppm for the entire photoperoid
Add 2-3x a week KNO3 (1/3 teaspoon)
Add 7-8mls of traces 3x a week
Add some Fleet enema or KH2PO4, 3x a week(roughly 2 rice grains worth or 3-4 drops)

Don't trust the NO3/PO4 test kits.

That should take care of most issues, give it about 2-3 weeks to see real improvement and tank balance.

Regards,
Tom Barr

[resk]

you are referring to the dosing after the blackout ?

i don't want to dose anything during the blackout right?

i use lab chems to make my fert solutions, therefore

i'm fairly certain my quantities are accurate

ive measured my NO3 solution such that 1tspn = 7.50ppm of NO3

ive measured my PO4 solution such that 1 tspn = .75ppm of P04

so ive been adding 1/2tspn of each at water changes, then another dose of each 3 days later

[djlen]

How deeply are your root tabs buried?
Have you done anything recently that could have disturbed them?

Len

[resk]

they were more like 'root granules', sort of like gravel ?

the directions read like:

place 1/2 aquarium gravel, then place root ferts, then lay second 1/2 gravel on top.

so i did as best i could to spread the stuff out and get it down into the gravel

i disturb the gravel a little (top 1/2 inch) when i vaccum

but i take extra care not to mess up my rooted plants or dig too deep anywhere

my vac is a little custom eheim upshoot that with an eheim intake strainer cap on the end, so i can get close to plant leaves without them getting sucked up or mangled/cut from the suction

[djlen]

If, after Richer's suggestion of the black out, the BGA comes back, it could be that there is a problem with these root tabs/granules working their way to the surface of the substrate.
The black out will kill what's there now.
Yes, Tom was referring to dosing after the black out is completed.
Do a large water change and clean up what you can. Raise spray bars and turn off CO2. Cover for 2 days. Uncover and do another large water change and re-cover. When black out is finished do another large water change and add back the ferts as described by Tom above.
If during these water changes you can do a complete(not necessarily deep) vac. job on as much of the substrate as possible, this would be a good idea.
Resist the urge to feed the fish during this process. They will be fine for the duration.

Len

[resk]

its difficult to tell about the root fert granules,

whether there are some sitting on the surface of the gravel..

my flourite is red / brown and the granules were also

i will be sure to do a good job with the gravel vac

[bortsamson]

maybe sound like an odd question, but I had a similar outbreak awhile back, looked to be blue-green, but not quite the same. I was able to remove it manually and such, just like yours, and it only happened to me after I changed my lighting setup to have my brighter light up at the front.
Now, I thought that if I stopped dosing ferts for awhile to let the plants soak up any excess nutrients, it actually got worse.
So I did a partial blackout, just had one row of light on for a couple days and went back to dosing my ferts, and also added some floating plants, duckweed I believe, and now I just have the "good" algae. Ya know, the kind that makes the tank look natural.
So, that worked for me, just keeping the lights low and upping the ferts to feed the plants. But also, some to think of it, I reduced my feedings as well.