247Plants

Well just an update on my tank....

After weeks of the green dust algae my glass is 90% gone and clear except for the white residue it leaves.....It was a tough one to wait out but im glad I did!

Sucess!!! Thanks Tom Barr even though he wont see this!

Zapins

My ottos really did a number on GDA. I have 9 of them in my 55 and they keep the place squeaky clean

banderbe

Ottos eat all your GDA?? I have three in a 29 and they don't even make a dent.

Also for those without the patience for Barr's method, I seem to have found something that seems marginally effective.

Overdose Excel to your tank and then immediately after you do that scrape all the glass- I use a credit card. I thought this might work to kill lots of the spores and it seems to because this week the GDA is coming back way slower, but alas it is still coming back. I am going to repeat this process and see if over a few weeks I can't eradicate it completely.. I doubt it will work.. but it's worth trying.. I just couldn't stomach looking at my poor tank all covered with green funk on the glass.. was too much to handle for more than a couple weeks..

Zapins

Well no, they did not eat all the algae. I first reduced intensity and duration of light. Then after a few days the algae started to fizzle out in most areas in the tank. However it lingered up near the top of the tank where the light was most intense. Then I added ottos.

The ottos ate the remainder and since then it has not come back. So the algae took a beating from less light and then the ottos ate the rest of it and I assume keep it from growing up near the top.

What a horrible algae. I am soooo glad it has gone... It really was painful to see it every day...

Gumby

Interesting you say this. I let the GDA get to almost the end stage... Thick film on the glass that swayed in the current, then it started to die from the top of the tank down, just turning white. The "tufts" of it on the driftwood and what was growing on the plants had started to bleach out too. So I scraped it off the glass with a credit card and did a 3x OD with Excel. I was thinking "hey, Excel worked for BBA, I'll try it on this crap."

I'll let you know how it went. I won't be around to see it personally, as I'm moving, but I'll ask my mother to give me a report on how it's doing.

"GDA" is exactly what I'd call this stuff... but sometimes the GD doesn't stand for "green dust," if you get my drift!

John P.

I've found this works to lessen GDA

1) Let the GDA build up,
2) Scrape the glass,
3) Do a large water change
4) Stop EI dosing/add only micros and potassium
5) Repeat 2, 3, & 4.

Ljeto

As some suggest, lowering the light does help prevent/slow down GDA. On the other hand, how do we grow light-intensive plants? Specifically, I have HM (grows like weed), some HC, and as of recently glosso (it's a 375 L / cca 100 g tank). In my earlier (lower light) set-ups I never had GDA problems, however, now with lots of T5s, GDA is my biggest enemy.

And just to share with you, Alternathera R. seems to be a real magnet for this menace - Alternathera grows fast, but only the newest leaves are not plagued with GDA. I am at a point where I am considering kicking it out altogether. I am hoping that once GDA goes off the glass, it will also leave Alternathera alone.

Ljeto

I would like to join the club of those who kicked-out GDA, using the 'do-not-disturb for 4 weeks' method. After 1 month, I wiped the glass, did 20% water change, and 10 days now my glass is spotless (well maybe a few dots of GSA). GDA in some form is still on my rear glass, but I don't mind.

I still have a minor case of BBA, but CO2 and Easy Carbo should take care of that.