Amazon Swords problem

[markdarren]

Tank Size 48x18x15.
PH 7.2.
AMM 0.
NITRITE HIGH.
NITRATE 10.
FILTERS FLUVAL 305.FLUVAL U4.
2 X 54WATT T5 Lighting on for 9hrs
TETRA SUBSTRATE (USED 23 KG)
GRAVEL
CO2 PRESSURE 15 BUBBLES PER MIN (JBL)
4 DROPS PER DAY FERROPOL 24 (JBL)
Dropper (4dkh solution 1.5ml. & 3 drops of bromothymol blue) lime green colour shown on dropper which i have read that this should be correct
Started fishless cycle. I now keep adding 2ml of ammonia each day
I have a timer on the co2 system which switches the co2 off 1 hour before the lights go off and it is switched back on 1 hour before the lights come back on
Several Plants bought on the 13/02/10
I have noticed that the amazon swords are all showing brown spots in only 3 days.Please could anybody tell me where am i going wrong

 

[bazz]

hi mark,
if you bought your amazon swords from a shop, i would imagine that it is die back of the emersed leaves where the plants have been grown hydroponically in the nursery. i personally remove all of these prior to planting, leaving just a few or the smallest centre leaves. this is perfectly natural and they will soon recover if conditions are good.
cheers,
bazz!

 

[markdarren]

Thank you for your advice.I thought that i was doing something wrong