Troubles with Rotala Rotundifolia and Pogostemon Erectus

Hello,


I have a 47g planted tank, it's been set up for about 6 weeks. Things are growing reasonably well, but I'm unhappy with the way my rotala rotundifolia (I hope I got the name right) and pogostemon erectus are developing. Rotala looks like its trying to make lots of new shoots but they are all stunted. Pogostemons just have stunted growth.


About the tank: I have pressurised CO2 running at 1-2 bubbles per second, I've had it on a timer, stopping it at night till 2 days ago, when I was advised to not turn it off as it causes ph swings. I'm dosing fertilizers from a brand called Vimi according to EI dosing, I'll post their composition at the end (numbers are in ppm, as the producer says on their site) The lights are from an LED lamp of 90watts (it has 6500K leds, 4000k leds, 2 red leds and 4 blue ones) but only keeping it at @60%, which should be @7000 lumens. I know lumens are bad for telling light for plants, but I have no way of getting a PAR meter for those readings. The water in my area is fairly hard (kH test tells me 11-12, ph is @7.5 in my tank with the co2). [TABLE=border: 1, cellpadding: 0, cellspacing: 0]


[TR]


[TD]K[/TD]


[TD]23000[/TD]


[/TR]


[TR]


[TD]N[/TD]


[TD]3470[/TD]


[/TR]


[TR]


[TD]P[/TD]


[TD]1000[/TD]


[/TR]


[TR]


[TD]Fe[/TD]


[TD]1800[/TD]


[/TR]


[TR]


[TD]Mg[/TD]


[TD]625[/TD]


[/TR]


[TR]


[TD]Mn[/TD]


[TD]375[/TD]


[/TR]


[TR]


[TD]B[/TD]


[TD]175[/TD]


[/TR]


[TR]


[TD]Zn[/TD]


[TD]37,5[/TD]


[/TR]


[TR]


[TD]Cu[/TD]


[TD]37,5[/TD]


[/TR]


[TR]


[TD]Mo[/TD]


[TD]12,5[/TD]


[/TR]


[TR]


[TD]Co[/TD]


[TD]3,75[/TD]


[/TR]


[TR]


[TD]Ni[/TD]


[TD]1,25[/TD]


[/TR]


[/TABLE]


Here are some images of my tank with the plants in question:


http://i.imgur.com/nEA29jz.jpg


http://i.imgur.com/54aJF8B.jpg

 

Regarding root tabs - I don't use them but the tank has fertile substrate under the volcanic gravel. It's something from Tropica - http://tropica.com/en/plant-care/substrate/. Tank is barely 6 weeks old, so that substrate is definitely not depleted.


I'm not concerned about the speed of growing, but about it's shape. When I bought them they had a nice rosy tint to leaves and generally properly sized leaves.


Regarding light, I'm confused. Some people tell me it's too much, others it's too low :S .


I'll try the reducing fertilizing and increasing my co2. I'm just wary about leaving co2 that high during the night - and again I'm confused if it's better to shut it off at night or not. Some people say shutting it during the night will cause ph swings, and on the other hand having it at 2-3 bbps is worrying during night time.