aww thanks Primo!! That is helpful! I wondered why one of my wisteria was skinny at the bottom but doing well at the top... I will definitely not be afraid to trim it now.
And no that's not the pink plant.. I'll take a pic of it for people to identify. I've stripped most of the stuff out and found the source of my ammonia problems. The rocks I kind of laid on top of each other which was a really, really stupid idea as gunk has just collected underneath the cracks of both and to make matters worse I thought it was a great idea to put a plastic bridge behind the rocks for the fish to hide in if they were scared. Umm, really stupid as it was just basically a gunk catcher! I also didn't bury the rocks in the substrate but placed them on top of the dirt so basically.. gunk city underneath them.
I had to move the bridge to catch my corys and the state of the water after that was unbelievable. Even though I was syphoning out 90% of the water to keep the ammonia out daily I couldn't work out why the fish seemed to be stirring up stuff at the back even though I was cleaning the substrate daily. Now I know.
So today I will clean it out yet again and plant the plants in the dirt again until I get back from my holiday and then get some new substrate and basically set up something more appropriate.
My little babies (corys) did not look happy in the community tank at the pet shop at all which has made me sad but at least they will live! I won't go buy them back later, I think just one betta for the ten gallon will be more than enough.
I am definitely interested now in setting up a larger tank, and corys will be on my shopping list. They were awesome. I know I've done the right thing now though, the tank had no chance how it was set up. It would have been ammonia cesspool forever.