So after spending yet another week trying to save my dying plants I have had some good signs!! taking in the advice I received here I upped the light levels to 12 hours a day and today I sourced 5kgs of pebbles to add to the tank to bulk up the substrate - I took the plants out of the pots. I syphoned the water out of the tank and through aloosely woven section of linen to catch any plant matter and put it in a bucket out of the sun, I took out the exsisting substrate and put it in the bucket of water. I rinsed the new rocks in water and then placed them in the sun to dry. I trimmed off any dead/dying leaves on the plants and re weighted them with plant anchors then everything went back into the tank. Firesong has lost his stem glasses for now and has received a bit more natural look to his tank - as much as I liked the glass and pink it showed guck really badly .