What am I doing wrong though to even loose the "Easy to Maintain" Plants.
Am I not using enough fertilizer?
You may be using too much fertilizer. What fertilizer(s) are you using, and how often do you dose?
Are my Fish / Snails Eating the Plants?
Could be. What kind of fish and, more importantly, what kind of snails are in your tank?
Do I need to feed my Fish more if so to stop them from eating the Plants?
If your fish are eating your plants to sustain life then, yes, you need to feed your fish more.
Am I doing to many or too little Water Changes?
Don't know. How often do you do a water change?
Are my Lights on too long or not long enough?
How long are your lights on? I shoot for around 10 hours a day, unless I notice the algae breaking out. If I notice that, I cut back on ferts and hours of lighting and wait for the algae growth to abate. Then when I lengthen the hours of light, I do so gradually. As for ferts, I try to do less than I was doing before or lengthen the time between applications.
There has to be something to Fix this.
Some plants prefer water with a higher pH and greater hardness, while others prefer softer more acidic water. Also, some plants require lots of light. If you can't provide it, the plant looks pitiful and may eventually die. You may need to do more research on what specific plants prefer. If you have an African cichlid tank (harder more alkaline water), you won't have much luck growing plants that prefer softer, more acidic water. By the same token, I can't seem to grow water wisteria no matter what, so I accept that fact and move on to others I can grow. Also, I've found that it takes about 4 - 6 months for a newly planted tank to take hold. During that time, some plants die, some take off, but most just seem to stagnate (meaning, they don't seem to do much except maybe look a little worse than when I planted them). Then one day I look at the tank, and lo and behold I realize the plants are starting to come into their own. No, they don't suddenly look lush and fabulous, but I realize they're growing and the new growth looks good. Some of the older original leaves look pretty pitiful by comparison. They may have some holes or tears or they may be kind of spotchy because of algae.
I am doing something wrong and I need to figure it out and figure it out Fast.
"Have patience, Grasshopper."
What is the usual cause for a "Melt" of a Plant?