Problem with Nymphoides sp "Taiwan"

[virgojavier]

Dear All
I have set up my tank at the beginning of November 2012. Nymphoides sp "Taiwan" was one of my first plants and it grown very fast without any problems in my tank besides the fact that I had a very poor lighting (11W in 54l tank), poor gravel mixed with aqua sand, no CO2 and no ferts.
At the beginning of January I have bought Tetra Optimat CO2 kit and started my advanture with Co2.
Week ago I have upgraded my lights to 2x15W Arcadia T8 (natural tropical) and by that I am achieving somewhere around 2.3 WPG which according to this forum is somewhere in the Medium range.
My CO2 concentrations are around 30ppm.
Here are some other parameters:
NH3 - 0
NO2 - 0
NO3 - less then 5
pH - 6.6 in the morning, 6.7 during day
Temp - 24.7
kH - 3
GH - 7
Lights are on for almost 12 hours per day.

On monday I have started playing with ferts, maybe this will help.
Made 2 stock solutions, one for macro, one for micro
Macro (in 500ml DI water)
- 15g of KNO3
- 5.8g of KH2PO4
- 15g of MgSO4*7H20
Micro (in 500ml DI water)
- 12g of CHelated Trace Elements
- 2.8g of Ascorbic Acid

Dose:
Mon 20ml Macro
Tue 10ml Micro
Wed 20ml Macro
Thu 10ml Micro
Fri 20ml Macro
Sat rest day
Sun water change

At the moment my Nymphoides looks like this. It stoped growing and looking very poor.



Please advise... what to do. Where I have made a mistake?
Lucas

 

[ceg4048]

Hello,
Your mistake was assuming that this is true=>

My CO2 concentrations are around 30ppm

The plant is telling you that you do not have enough CO2. Add more...much more...

Cheers,

 

[virgojavier]

Thx ceg4048. Yup you are right. I overestimated this value.
I have just done the JBL CO2 test which is showing green colour (20ppm).
My pH is 6.69, KH 3dh, so applying the CO2 calculation I am getting somewhere around 18.8ppm of CO2...
I am afraid that my Tetra Optimat is a bit rubbish🙁 need to start thinking about something more advanced.

Lukasz

 

[Ady34]

You could revert back to your old 11w light, that way you have a little more leniency regards co2, 20ppm may well be enough with the lower light. I run an 11w light over my 55l CRS nano.
Cheerio,
Ady