Well, I just got back from the LFS. Some good news too. Everything they tested came out good they said, so it's not my water. They explained how cardinals are one of the more delicate fish and it was/is probably just that and nothing that I did.
Also, it turns out that whenever they get new cardinals in they quarrentine them for a day to make sure they aren't too stressed and watch for any illness.
tstenback, you will be happy about this part too. The guy that helped me when I was there said not to use the rid-ich. He said you only want to use something like that if you know there is a problem and more than one fish is experienceing problems of it. Kinda wish I hadn't bought the rid-ich, although it was only 2 bucks and it may come in handy in the future and then I won't have to worry about going to buy it.
He said to give the fish another day or so to perk up and if it doesn't start looking better to euthanize it. He said it would be better to do this than to possibly cause problems for the other fish which seem to be healthy.
And, he asked how long after I bought them did they die. I said one the first night and the second on the 6th day. So, he offered to give me a refund. I was about to bring up the guarentee, but he did it for me. He didn't even ask if I had the fish, just for my reciept (which he didn't even really look at). So, that made me a little happier.
He said he would give me a refund instead of the fish because (just like I was thinking) now is not the best time to add more fish. He said to wait a week after things are looking good again before I add any more fish.
And the last comment I would like to make is to say thank you tstenback, and everyone on this forum. Being new to fishkeeping, this site and the people on it have proved invaluable. Just the advice that I got from this post alone from luxum and tstenback helped greatly when I went to the LFS. I actually knew what I was talking about.
The guy at the LFS seemed rather enthused that I semi knew what I was talking about and that I keep up on my maintence. I told him I did a small waterchange when I saw the one sick fish and that I was going to do another one and a gravel vacuum today. Turns out he was just about to recomend I do this. He also asked how often I feed, and I said twice a day but I was thinking about cutting back to once a day (look at one of my earlier posts in this thread) and he said, exactly.
He said it was good I have done my research and I should have very healthy tanks if I keep up the good work. He also asked where I did my research and I told him about this forum.
I think that the advice I have gotten in this forum, as well as reading other peoples posts (and some outside research too), has helped me avoid a lot of trouble that newbies typically make. Sure, I have lost 2 fish in the past week and have another one that is ill, but as far as the opinions I have gotten so far I am doing everything properly and it was nothing I could have done.
So, I just want to thank everyone on this forum for all the advice and opinions they have given. It really is a great resource for anyone, new or old to the hobby to be able to check out this site.
Thank you
Jiffy