Hi again all, I'm having a bit of trouble and really stuck on what to do.

Let me start it off with todays news.

I woke up to find my lovely 2 day old L200 plec... dead:
(IMG:http://xose.co.uk/discus/Photo0095.jpg)

To which I panic'd even more, and did a water test, to which came back:
Ammonia - 0
Nitrite - 0
Nitrate - 5
pH - 7.0
(IMG:http://xose.co.uk/discus/Photo0100.jpg)

The tank is a Juwel Vision 180, running TetraTec EX1200 External Filter, Pea Gravel, 7'ish live plants (not over crouded though) with airstone.
Temperature is at 28.8*c ... It was 30.0*c however I found the discus where breathing rather heavy and the plants didn't look how they used to, dropped it a little and seems better!

The main problem is with the Discus (despite the death of the new plec)
The turqs...pigeon bloods...yellow malbroughs seem perfect, eating well, solid dark "normal" poo's... however my two lovely Red Melons will not eat, show no interest to, sit at one side of the tank, no discolouration, but they are getting thin, haven't eaten in months (from my recollection)
And they are having white poo's.

I used Kushuri (sp?) Wormer Plus 3 weeks ago.
I used Heximita (sp?) last week on them to see if that would flush them out and get them back on track.

No use.
All this week I've been doing 15-20% (roughly) waterchanges everyday to see if it spices them up a little.

Still nothing.

If anyone has suggestions it would be greatly appreciated, It's very upsetting seeing them like this...

I have Tetra Prima, Frost Dried Bloodworm & Frozen: Bloodworm, Brine Shrimp, Tropical Quartet, Chichlid Mix, Discus Food.

And I have ALOT of medication which I stocked up on (lol)

Thanks in advance as I know how decent people are on here and give very good advice.
Stephen.