reintroducing bga??

fosteder

Guru Class Expert
Feb 3, 2005
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Rochester, NH
I really don't mean to beat a dead horse, and I know this subject has been covered many times, but I am at my wits end with the BGA issue. I don't want this thread to turn in to a "how to treat BGA in my tank thread". I know how to do this. I have followed every step of advice. I believe everything Tom has said in treating this. I have dosed KNO3 before blackout and after. There was NO light getting into the tank or filter or anywhere during the blackout. I believe that the blackout and KNO3 dosing killed the BGA in the tank. But it still returns. I know that the KNO3 levels in the tank were never low. I was dosing .25 tsp three times a week, never missing a dose (it is a 20 gal tank). Plant biomass is medium.

I have been told that you won't get BGA unless your KNO3 levels are low, but that once it appears it doesn't matter what the levels are, the only ways to get rid of it are Maracyn or blackout. I have done this. Tom has said that once you correct the issue (low KNO3) and kill the BGA it will not return (assuming you keep up with KNO3). So i am thinking the only logical answer is, that I am reintroducing BGA into the tank from an outside source. If I did everything correctly and had a BGA free tank with good NO3 levels and I added water with BGA already in it, would it thrive and multiply? If this is true, what is the most likely situation?

1. I keep adding it with a piece of equipment (python water changer, net, scraper). In my mind this is most likely. I will do a bleach wash of everything that goes into the water (I assume this will rectify this situation). Can BGA live without water? (the net was completely dry)

2. It is coming in through my water source. Is this possible using municiple water, wouldn't the chlorine kill it?

3. It is airborne......run for your lives. (I only list this to be ridiculous). :D

Am I missing something? Thanks for any ideas or suggestions.
 

imatrout

Prolific Poster
Apr 4, 2005
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Re: reintroducing bga??

I have a similar problem. I've only done a single blackout that appeared to work very well. Yet, four days later i am seeing some traces begin to form. My NO3 is in a good range, but I noticed testing every day that it was not diminishing...no uptake. So I wondered if there was another limiting factor. I "think" it's not the NO3 that stops alae growth, it's the general high metabolism of the tank inspired by the NO3. If there is some limiting factor that keeps the tank metabolism slow, then you probably will get algae no matter how much NO3 you have. In my case, I "think" my limiting factor is K, Potassium. From what I've read, it plays an important role in fueling plant metabolism. After fiddling with the Fertilator with my dosing regime, it looked like the only nutrient that could be underdosed is K. I have upped the dosage of K with Flourish Potassium just yesterday. I'll let you know if it yields results. Note: In MY case it looks like the limiting factor is K, but retarded metabolism I think can be caused by other limiting factors as well, the most notable one being CO2.
 

srozell

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Jan 24, 2005
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Re: reintroducing bga??

Wouldn't dosing KNO3 be supplying Potassium? Or is this potassium not usuable?
 

Greg Watson

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Jan 23, 2005
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Re: reintroducing bga??

fosteder said:
I believe that the blackout and KNO3 dosing killed the BGA in the tank. But it still returns. I know that the KNO3 levels in the tank were never low. I was dosing .25 tsp three times a week, never missing a dose (it is a 20 gal tank). Plant biomass is medium. Am I missing something? Thanks for any ideas or suggestions.

Dosing 0.25 tsp is only adding 11.34 ppm of Nitrate to your 20 gallon tank ... I've often seen my tank suck down 10 ppm daily ... are you sure you are not bottoming out the nitrates several times a week?

Tom recommends that dosing rate 3-4 times a week ... I'd up it to the four times a week and you didn't say what you were dosing for traces, but I'd up that to at least the maxium recommendation that Tom recommends of 5 ml at least three times a week ...

If you are doing your water changes on a regular basis, it won't hurt you to at least give it a try by dosing closer to the Tom's dosing recommendations ...

Greg
 

imatrout

Prolific Poster
Apr 4, 2005
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Re: reintroducing bga??

Greg,

My problem is that the plants are not using the NO3. When I reset at Tom's recommended dosage, I test at 30 ppm. Then I test every day and it only reduces by a barely measurable amount, maybe 2-3 ppm. I have a hard time adding another 25 ppm every other day when the plants only consume 2-3.

I know I have some limiting factor going on and the only thing I can't test is K. I have a heavy fish load as well which could also be causing K to be the limiting factor. We'll see soon enough. I'm adding 2 ppm daily of K until I see a distinct move in NO3 uptake. If I don't see a move by Sunday, my WC day, I'll reset and try somthing else. By the way, my params are:

GH=20
KH = 16
Ph= 8.1 tap, 7.2 with CO2
CO2= 28 ppm
NO3 = 25 ppm
Lights = 2.7 wpg
Photo period= 12 hrs @ 1.35 wpg, 5 hrs at 2.7 wpg mid-cycle
Fe= not measured lately
PO4= not measured lately

As Tom says...one thing at a time.
 

fosteder

Guru Class Expert
Feb 3, 2005
123
0
16
Rochester, NH
Re: reintroducing bga??

Greg Watson said:
Dosing 0.25 tsp is only adding 11.34 ppm of Nitrate to your 20 gallon tank ... I've often seen my tank suck down 10 ppm daily ... are you sure you are not bottoming out the nitrates several times a week?

Tom recommends that dosing rate 3-4 times a week ... I'd up it to the four times a week and you didn't say what you were dosing for traces, but I'd up that to at least the maxium recommendation that Tom recommends of 5 ml at least three times a week ...

If you are doing your water changes on a regular basis, it won't hurt you to at least give it a try by dosing closer to the Tom's dosing recommendations ...

Greg
You're right Greg! .25 tsp only gives me 11.34 ppm. Maybe I was dosing .5 tsp and made a mistake when I wrote this post. I can check my dosing log that I keep. I was/am at work when I write these so maybe I made a mistake.

If I didn't make a mistake, I guess I know what has been happening huh? Good catch Greg. Thanks. :eek:

Is it possible to reinfect your tank from nets, pythons...etc?
 

fosteder

Guru Class Expert
Feb 3, 2005
123
0
16
Rochester, NH
Re: reintroducing bga??

Greg, The more I think about it, the more I think you hit the nail on the head. The BGA was gone for 2 months at least, and over the two months my plants obviously multiplied like crazy (I think I went from have 5 Dwarf Sagg to having about 40...hehe). I must have just been bottoming out the NO3 (even if I was dosing .5 tsp KNO3). Don't I feel stupid...... :rolleyes:

Just a newbie making newbie mistakes. I won't make that mistake again. :mad: