Help with BBA

[marchmaxima]

Hi all

Seems like I'm working my way through the algaes!

First, I had cyano bacteria and GSA. With the suggestions on this thread here http://www.aquariumadvice.com/forums...er-103131.html I have now been three weeks and I have had no more cyanobacteria grow (yay! thanks guys!). The GSA has returned a bit after my scouring the tank but in much smaller amounts.

But it looks like I've now created an environment that attracts BBA! Asmallamount of black furry yukness appeared around a week or so ago on the glass at the back and ths week, more has appeared on one of my driftwood pieces.

Current params.

Amm & NitrITE = 0
PH < 6.0 (I can't measure any lower)
NitrATE 40ppm
Phosphate = 3ppm

Dosing routine: 3 weeks ago I changed my routine (see above thread as to why). It is now as follows:

Potassium Suphate - 20ppm.

Potassium Nitrate - 10ppm - I'm aiming to have a nitrATE level of 20ppm post-PWC. Being a 15g tank, it goes up over the week to usually somewhere around 40ppm when I do the next change.

Potassium Phosphate - 5:1 ratio of Nitrate to Phosphate.

Plus I dose 1ml flourish excel comprehensive.

I do all my dosing weekly when I do the obligatory 30% pwc.

I don't inject CO2 as it's a low-light setup. I was doing some reading and I read that to prevent BBA, you should aim to keep around 15ppm NitrATE and 0.5ppm phosphates. I can do that, but this is the conditions I had before. In other words, this is the environment that appeared to be the cause of the cyano & GSA to thrive.

I scrub the BBA, but just like the cyano/GSA, I need to address the underlying cause to prevent it returning.

HELP! any ideas?

[marchmaxima]

Also, on a related matter..... What is my new dosing routine doing to my Java fern??

[Purrbox]

How often are you dosing each of the above? Once a week? Daily?

[jsoong]

I think your Java fern is having babies!! Wait a few weeks & the brown spots should start to sprout roots & little baby plants will start to grow. So they must be liking the new regime.

I must say I am not an expert with BBA - although I am very familiar with it ... having to struggle with the thing over a year! I have tried just about every method I've found on the net (except for dosing with H2O2) .... What worked finally was to super heavily planting the tank with fast grower, and decreasing my ferts. I assume this is depleting something the BBA needs.

For small amounts, it is best to remove all the affected leaves (they will die anyway once BBA covers it). Dosing Florush Excel (NOT the comprehensive) at the "loading dose" daily for 3-5 days also will kill BBA, but some plants will also be killed. Blackouts never worked for me ... although someone here had success with blacking out the tank for 2 weeks! Of course, once your got rid of the stuff, you still have to correct the root cause.

[marchmaxima]

weekly dosing. I'm doing it at the same time as the PWC.

I'm not convinced on the Java fern having babies. My Java fern has sprouted new leaves with roots at the end of larger leaves, and it's never looked quite like this. These brown spots cover the affected leaves, they become a hole, and take over the leaf until the only thing left of the leaf is the skeleton.

I'm starting to wondering if the higher phosphate level is "burning" the plant, for lack of a better term.

[Purrbox]

Sounds like a Potassium deficiency. Pinpoint holes that expand like that are a classic symptom. You might want to up your Potassium dosing.

[marchmaxima]

okay, and I might also lower the phosphate dosing. See how that goes.

[FishEggs]

the same thing happened to my java ferns and it seemed to spread from one side of the tank to the other and wiped out all but one of my ferns. it didn't matter if it was a new leaf or an old one. i would remove any leaves with spots on it since the leaf will die anyway just in case it helps. this happened to coincide with a bout of what i believe was staghorn algae that i got. i tried increasing my excel dosing to kill off the algae and that seemed to work but i still lost most of my ferns.