Black rust-like algae formation - Algae

Ro_land · 01-23-2008, 04:53 AM

I have a 200liter freshwater community aquarium with a year and a half old setup. In the last two months I found some black/grey formations mostly on my foreground plants, close to the bottom like Glossostigma and Sagittaria (see photos) but also on the wall of the aquarium. A part of it comes off by scraping with the finger.
The aquarium is not overpopulated (few rasboras, neons)
I use CO2 addition, macro (KNO3 and KH2PO4) and micro nutrients with 5x30W light (2x865, 2xOsram Fluora, 1x830).
My test readings are:
KH = 8
PH = 6.85
PO4 = 1.0 ppm
NO3 = 15-10 ppm
Fe = 0.1-0.2 ppm

Has any of you seen something like this? Any ideea?

Newt · 01-23-2008, 09:23 AM

I have the same problem. It is difficult to control. It is a type of black algae (not the brush type) and belongs to the red algae family. Do not use iron >>> keep it at non-detect levels. SAE's seem to keep it under control but do not eliminate it. Remove heavily affected leaves thru pruning. I read an article on this at www.thekrib.com where the author recommended having the KH higher than the GH. It didnt do much and I went back to a GH of 3 and KH of 1 to 2.

Keep your light bulbs 'fresh': ie linear fluorescents changed out each 6 months and CF/PCs annually. I'd push your CO2 concentrations up some and dont let the NO3 run low as then it will really spread.

Ro_land · 01-30-2008, 04:52 AM

I am trying to keep at a lower level the iron and macro fert levels. Let's see what happens.
Any other ideas of a possible cause for this algae growth?

Riney Key · 02-14-2008, 12:18 PM

I too am experiencing the beginning of brush algae. I tried a couple of commercial products, but they have had no effect whatsoever.

The 20G aquarium has been established for several months and most of the plants are healthy and require regular pruning. I use Ro water only. I use DIY CO2. The aquarium has a potting soil/red flint substrate. Everything is healthy and growing nicely except for that patch of brush that is now growing.

I have dosed this tank with PPS-Pro right from day 1. I've learned about PPS-Pro here on APC.

So now, to figure out how to stop the brush algae, I'm experimenting with cutting down the iron aspect of my PPS-Pro dosing.

Also, someone on here suggested Flourish Excel. I might try that too.

I read somewhere on thekrib that copper might kill that type of algae straight out. I'll try that too as a last resort. But first, I'll give the iron reduction a chance over a period of time.

Newt · 02-14-2008, 03:13 PM

Copper might kill your fish and plants as well.

Dont feed any iron and limit phosphate until under control.
Push your CO2 to 30ppm and keep steady.

If the copper doesnt kill your plants and or fish the dead algae may.

Riney Key · 02-14-2008, 03:20 PM

Quote:

Originally Posted by Newt

Copper might kill your fish and plants as well.

Dont feed any iron and limit phosphate until under control.
Push your CO2 to 30ppm and keep steady.

Yeah, I won't be going bonkers with copper, but might try a bit of it.

For now, like you said: No iron.

I'll check phosphate.

My assumption is that the CO2 is high enough. I have 4 yeast mix bottles on the tank and the output is fed into reactors.

Carlos1583 · 02-14-2008, 05:07 PM

I have the same issue...but how do you deal with plants that need high iron? Do you fix the algae first and then go back to normal dosing? I'm also trying to get a hold of some SAE but can't find any.

hoppycalif · 02-14-2008, 05:27 PM

Iron doesn't cause algae, nor does phosphate. A lack of CO2 certainly encourages algae, and a too sparse plant density also encourages algae, plus, having too little water circulation in the tank causes local low CO2 concentrations which encourage algae. I suggest you get a drop checker so you can verify that you have enough CO2 in the water, and make sure you have enough water circulation that you can see every plant swaying in the flow.

Newt · 02-14-2008, 06:42 PM

Quote:

Originally Posted by hoppycalif

Iron doesn't cause algae, nor does phosphate.

There are a lot of articles and studies out there that disagree with this and personal experiences.
Excess Fe and PO4 are known to be problematic in the aquarium. By limiting them temporarily it should rid the tank of BBA.

You dont need a drop checker to find out what your CO2 is.

Take a look at the attached spreadsheet.

Riney Key · 02-14-2008, 07:21 PM

Quote:

Originally Posted by hoppycalif

Iron doesn't cause algae, nor does phosphate. A lack of CO2 certainly encourages algae, and a too sparse plant density also encourages algae, plus, having too little water circulation in the tank causes local low CO2 concentrations which encourage algae. I suggest you get a drop checker so you can verify that you have enough CO2 in the water, and make sure you have enough water circulation that you can see every plant swaying in the flow.

I do have enough CO2. I don't need to do a test for that. I compare with another blooming aquarium that is twice as large in which I inject 1/2 less CO2. I have gentle but good circulation too in all of them. My problematic tank is stuffed with plants. All plants in good health, some jetting small bubbles, except for a growing patch of that nasty brush algae. So none of those are the issue in my estimation.

I'm not talking about all kinds of algae. Only the specific brush algae: Feathery black-gray tufts that appear in some places.

Up until two days ago, I had been dosing with PPS-Pro. This tank also has a thick soil and red flint substrate. That's why the iron appeared to me as perhaps being a problem. Perhaps more than necessary. I'll start testing again and experimenting with everything I can think of and see where I'm at in a month...