tank after BGA

[yme]

Finally, I think that I am rid of the annoying BGA. It took some H2O2 (which destroyed the potamogeton wrightii and gayi as well as the elatine tiandra) and lots of waterchanges. So, I have lost a lot of biomass, due to the treatment.

First my settings:

Tank: 100x40x40
Pomp: eheim professional (containing just white foam)
CO2: pressurized, administration by wooden airstone
Substrate: amtra plant depot (1.5 years old)
Light (30 watt per TL):
1x Philips TL 840 (middle): 13.00-23.00
1x Philips TL 830 (middle): 13.30-22.30
1x Philips TL 830: 19.00-22.00
1x Philips TL 840: 19.00-22.00
1x Philips TL 840: 19.00-22.00
liquid fertilzer: 3-4x/week 8 ml flourish, 3-4x/week 8 ml flourish iron
pH: 6.4
KH: 4.0
GH: 6
PO4: 0.3 mg/l/day (the actual PO4 level in the tank is quite low, 0.5-1 mg/l)
NO3: 2 mg/l/day (NO3 levels are rising during the week, 17 mg/l directly after waterchange, to 25 mg/l after 7 days)
Conductivity: 480 µS
Water change: 60 litres per week, 30 litres of RO water and 30 litres of tap water (pH 8, KH 7-8, GH 8, 660 µS, NO3 10, PO4 0)



The plants are now growing just fine, but some algae is reappearing. Some dots of BBA are starting to appear and after a week the glass is covered by single stranded 2-3 mm long algae (fuzz or green dust).

I think that you guys suggest getting more CO2 in the water because of the following reasons:

-the algae
-enough NO3
-enough iron (nice green new leaves)
-likely enough micro´s.

Oke, my fish are not gasping for air, so I can increase my CO2. However, I would prefer to not lower my pH. Is it also possible to increase CO2 by adding some HCO3-? The pH/KH chart suggests just that. But I also read some posts in which it was suggested that plants do not like a very high KH. So what is the way to increase my CO2? What do you suggest?

Or are there even other options to improve my tank? (p.e. more PO4?)

And of course a picture of my tank:

I know, it looks terrible... but I finally decided to remove the echinodorus!

greets,

yme

 

[VaughnH]

Re: tank after BGA

I would change from dosing PO4 every day to dosing every other day, with the traces dosed on the other days, and increase PO4 dosing to .5-.75 mg/l per dose. I would increase NO3 dosing to 3 mg/l per day. And, I would increase CO2 until the fish start to seem distressed, then back off a bit. If you don't want the PH to drop any lower, add some bicarbonate of soda to raise the KH a couple of degrees, but dropping the PH shouldn't be harmful either.
I'm still struggling with my own algae and plant issues, most recently by adding some calcium, so I am hardly an expert at this. I do know that using test kits to determine the amount of nitrate and phosphate in the water is not likely to be accurate. It is better to just add what the plants need, and use the 50% weekly water change to get rid of any excess.

 

[aquabillpers]

Re: tank after BGA

In the interests of accuracy, I would say that many test kits are close enough to being "accurate" for most uses, in normal ranges. The ones I've used won't tell if nitrates are 60 or 70, but they will be close enough in the 5 to 15 range.

I don't like the idea of raising the CO2 level until the fish show stress. Given the variability of the reactions of different species, some will show no effect while others will die.

And, of course, there is EI, where you don't have to worry about test kits at all.

Bill

 

[VaughnH]

Re: tank after BGA

The alternative for CO2 "measurement" is to shoot for a 1 PH decrease due to the CO2 - measure PH in a degassed tank water sample, and shoot for decreasing that by 1 with CO2. This is more likely to be an accurate measure of CO2 than the KH/PH table is.

 

[Tom Barr]

Re: tank after BGA

I don't like the idea of raising the CO2 level until the fish show stress. Given the variability of the reactions of different species, some will show no effect while others will die.

And, of course, there is EI, where you don't have to worry about test kits at all.

Bill

I agree with not stressing the fish.
That is just a limit if all else fails and you cannot test reasonably.

But I've seen folks with supposedly 15-20ppm and gasping at the surface, there are other things beside the fish and CO2, a lot seems to do with the rate of degassing and surface movements/mixing in the deep section of the tank.

I suggest bumping the CO2 up by 0.1pH units and seeing if that solves the issue(and slowly and progressively doing so till you have good algae results, or if the fish balk first) rather than going to max level the fish can withstand.

I'm worried more folks will fry their fish in efforts to reduce the algae with cO2.

The other thing you can do, it use less light, that => less CO2 demand from the plants => more stable supply.

Less light gives you more flexibility and wiggle room on dosing and CO2, as well as trimming and other mainteance related issues.

Regards,

Tom Barr

 

[yme]

Re: tank after BGA

thanks everybody!

I lowered my pH by 0.1 and will see what happens.
I also don´t like the stressing of the fish idea. It just doesn´t sound right.

and just for the record:
-I am measuring my PO4 and NO3 by photospectrometer. also not completely accurate, but it gives you more information. So I calibrted the tests and find that the NO3 is rising but the PO4 is dropping. Therefore, adding more PO4 could possible help as well?
-for the moment it is not possible to dose nutrient every other day. I am dosing automatically by a home-made device. I have to buy a timer that can be switched on/off per day in order to dose every other day. I will think about buying such a thing....

greets,

yme

 

[Tom Barr]

Re: tank after BGA

I'd just up the PO4.

One thing you need to really really really really really really realize..........decline, increrases in the water column do not imply all the nutrient is being assimilated into growth of plant biomass.

Some is used by other organsims, bacteria etc, some is preciptated out, some is stored as luxury uptake inside the plant cell, uptake alone does not equate to plant demand.

But I'd prefer having a "fat" happy plant versus one getting only what it needs and no more.

Plants can get by with less CO2 also, but I also prefer them to have plenty and what we add certainly even if it's 15ppm could also be agrued to be "excessive" as well.

It's a fertilizer as well.

Regards,
Tom Barr

 

[yme]

Re: tank after BGA

hi tom,

I increased the amount of PO4 to 0.3 mg/l/day. What do you think how long it will take whether the desired result is obtained?

I do realize the remark about the changes of nutrients in the watercolumn.

One observation that I want to share is that during the H2O2 treatment and the subsequent melting of the plants, the PO4 level was getting higher every day instead of decreasing. I never experienced a "spontanious" increase in PO4, so I am not sure what to think about it. (except the correlation with the treatment of course)

greets,

yme

 

[Tom Barr]

Re: tank after BGA

hi tom,

I increased the amount of PO4 to 0.3 mg/l/day. What do you think how long it will take whether the desired result is obtained?

Hard to predict but you can always add more till you see a slight build up.
Beyond that would offer no benefit.

I do realize the remark about the changes of nutrients in the watercolumn.

One observation that I want to share is that during the H2O2 treatment and the subsequent melting of the plants, the PO4 level was getting higher every day instead of decreasing. I never experienced a "spontanious" increase in PO4, so I am not sure what to think about it. (except the correlation with the treatment of course)

greets,

yme

The PO4 should increase after such treatments, I would predict that if I did that.

This is due to the relase of PO4 from both the plants and the algae.
The stress and decay of plant tissue will cause the leakage in live plant and algal material biomass and then the dead biomass with leak the contents out, you also have reduced the uptake of PO4, so any inorganic sources of PO4 added will likely build up as well.

Sort of a 1-2-3 punch.

You could also add bacterial biomass PO4 sources in there as well as H2O2 is general biocide, it's not really selective except in terms of size differences of the plants and the algae.

Plants like Egeria will be more sensitive to such things like copper, H2O2 etc than say something like Anubias.
Egeria's leaves are thin, not cuticle really, 2 cells thick.




Regards,
Tom Barr

 

[yme]

Re: tank after BGA

ahh. leaking of unhealthy tissue. makes sense.

For the moment, I see that the plants are still growing fine, but that the are more and longer single stranded algae on the glass. I will keep the PO4 level above 1, NO3 was now around 30 (maybe a bit too much) and the pH at 6.3 with a KH of 4.

To my surprise I found a very small strand of elatine tiandra in the tank! So maybe (if the fish don´t eat it) I will be able to grow it back again. That´s what I´m gonna try. But my experience with this plant is that when I reduce the light, the plant will grow vertically instead of growing horizontally. Therefore, I am not prepared to reduce my lightning in order to lower the metabolism and prevent algae growth. After all, you are able to grow nice plants with high light and no algae! (and I don´t think that 2x 30w for 7 hours and 5x 30w for 3 hours is that much light)

So, I have to figure out which conditions are necessary in order to get rid of these single stranded algae under "high" light conditions.

greets,

yme