# Plant problems - new growth is going yellow



## David_S (Oct 20, 2010)

Hi,

I'm new here, and I have just started up a new tank. Its a big tank too - 375 Litres - 185cm long x 45cm wide x 45cm deep.

I've had the tank up and running for about 3 weeks, and I'm a bit concerned about the plants. 
I have planted the plants about 1 and a half weeks ago, and since then, some of the plants have grown new shoots in the top, but they have gone yellowish (the new growth). 

Can anyone tell me the cause?

The specifications are:

2 x AquaOne Fluorescent lights (90cm long each) - they are both single tube lights and are fitted with 36W pink Bio-tubes
Lighting is on from 9am in the morning til 9pm at night.
I have 110cm of air-bubbler tubing, but it only runs at night once the lights are off, and it turns off once the lights come on (in order to prevent eliminating CO2 during the day
Water temp - 25.5 - 26.5
PH of the water is 6.6-6.7
Hardness of the water is 6 degrees (or 100ppm)
I have 4 Otocinclus catfish, 2 peppered corydoras, and 2 bristlenoses (to get the cycling going)
The plants are planted in approx 5-7cm gravel, and the bottom 2-3cm of gravel has an aquarium grade Laterite mixed through it - in addition, I have also given the plants a dose of liquid fertilizer the other day too.
 Can anyone tell me whats wrong? Is there not enough CO2, not enough light, or not enough fertilizer???

Thanks for any help!


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## susankat (Nov 15, 2008)

I would say a little bit of each. Depending on what plants you have. Your basically in the low light range and by the sounds of it your plants need more light. Are you injecting co2 into the tank? If not you don't need to turn off the bubbler when the lights are out. What are you dosing with in the way of ferts? You probably aren't dosing enough of certain ones.


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## NursePlaty (Feb 5, 2010)

*Usually, if a plant goes yellow, its because of iron or potassium deficiency. I remember it happened to me before I suppplemented iron in my tank. Now, I add molding red clay to the bottom of my substrate and I dont have that problem anymore. I think API Leaf Zone also has iron in it if I remember right and you can use that for ferts.*


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