Fertilizers and Prunning

  • Thread starter evandro.carrenho
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evandro.carrenho

Guest
Hi,

I am running my tank with EI, although I test a few parameters weekly (still getting rid of testing).

Had green water issues in the past, but after solving it with UV, the tank is running relatively stable. I say relatively, because I have green water coming back right after prunning the plants, and need to turn on UV for two or 3 days.

Should I change (decrease) my dosing and CO2 injection routines after prunning?

Tank: 60 x 35 x 38 cm
Water change: 50% weekly

Lights: 4 x 24w turned on 9,5 hours
CO2: 3 bubbles per second with ADA glass counter

PH: 6,4 (day - during CO2 injection) - 7,0 (night)
KH: 3,5 - 4 dH
GH: 6 dH

NO3 (NaNO3): 11 ppm (3x a week)
PO4 (KH2PO4): 1,5 ppm (3x a week)
K (K2SO4): 15 ppm (3x a week)

Seachem Trace: 5 ml (2x a week)
Seachem Iron: 2,5 ml (2x a week)

Seachem Excel: 5 ml daily (except on friday)

Thanks,
Evandro.
 

Frolicsome_Flora

Guru Class Expert
Jan 12, 2007
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96 watts for only 20 gallons? dats a whole lot of light you got there, and id say that was a huge part of your problem.. 2-3 wpg for a MAX of 8 hours.

you shouldnt need to alter anything in your maintenance after pruning, unless your ripping out 1/2 the biomass.

also, counting bubbles to know how much co2 you have is no way to do it, what about different sized apatures inside each counter. You need a drop checker using a reference kh solution in it, its the only way your going to have any real idea of what your co2 is.

so, WAY too much light and possibly not enough co2.



evandro.carrenho;17928 said:
Hi,

I am running my tank with EI, although I test a few parameters weekly (still getting rid of testing).

Had green water issues in the past, but after solving it with UV, the tank is running relatively stable. I say relatively, because I have green water coming back right after prunning the plants, and need to turn on UV for two or 3 days.

Should I change (decrease) my dosing and CO2 injection routines after prunning?

Tank: 60 x 35 x 38 cm
Water change: 50% weekly

Lights: 4 x 24w turned on 9,5 hours
CO2: 3 bubbles per second with ADA glass counter

PH: 6,4 (day - during CO2 injection) - 7,0 (night)
KH: 3,5 - 4 dH
GH: 6 dH

NO3 (NaNO3): 11 ppm (3x a week)
PO4 (KH2PO4): 1,5 ppm (3x a week)
K (K2SO4): 15 ppm (3x a week)

Seachem Trace: 5 ml (2x a week)
Seachem Iron: 2,5 ml (2x a week)

Seachem Excel: 5 ml daily (except on friday)

Thanks,
Evandro.
 
E

evandro.carrenho

Guest
Inbalance in CO2 and light might be the issue, but then I would have algae trouble unrelated to the prunning event, wouldn´t I?

I don´t use a drop checker, but from my KH and PH measures above it seems that CO2 level is about right, and my plants pearl regularly. Although I notice that they pearl the most during the last third of the photoperiod. Should this be normal?

Yes, the green water appears when I perform larger prunnings, possibly reaching 1/2 of the biomass. In this event should I decrease the doses? Have you had experience with this approach?

Anyway, I will consider shortening the photoperiod.

Thanks,
Evandro.
 

VaughnH

Lifetime Charter Member
Lifetime Member
Jan 24, 2005
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Sacramento, CA
Green water is usually an algae bloom caused by a spike in ammonia in the water, and disturbing the substrate can give an ammonia spike. So, if you prune by pulling out the rooted half of stem plants and replanting the tops, then you are disturbing the substrate. If you have any substrate fertilizing or if you use ADA soil as a substrate, you should expect to be causing an ammonia spike when you disturb it. Also, not keeping the same level of CO2 in the water every day can also trigger such an algae bloom. A cheap drop checker can help you to keep the same correct level of CO2 in the water. Measuring KH and pH doesn't work very well for determining how much CO2 you have.
 

Tom Barr

Founder
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Jan 23, 2005
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In addition to what the experts have thus said: you should consider doing 50-70% water changes right after you do pruning.

This will help a lot.

Or if there is any issues, try 2x a week water changes till things stabilize.

Regards,
Tom Barr