New to Puffers, what's wrong with my little GSP?

[Babsrocks]

Hello everyone.
I am new to The Puffer Forum, I've been on another forum for years, but not many people over there are experience with puffers. So I was referred here. I hope you can help me.
I've been keeping fish for many years and have wanted puffers for as long. I did my research and am finally in a position to properly care for these wonderful little creatures. So I decided to get a few puffers last week when I saw them at the LFS. I picked them up the other day. I got 2 Figure Eight Puffers and 1 Green Spotted Puffer, they are also with 2 Bumble Bee Gobies. Everyone seems to get along and seem to be alert, curious, and active.
They are currently in my 15 gal quarantine tank (they will be moved to larger tanks as soon as I'm sure they are healthy). All are eating well, they've eaten snails (self bred), frozen blood worms and frozen krill, they also actually ate some Tropical Crisps that were intended for the Gobies, I was a bit surprised, but maybe they were fed that at LFS.
As I always do with new fish I started treating with Melafix and Pimafix right away. All of the puffers had pieces of fins missing which I've heard is common with transportation etc. Yesterday I noticed they have Ick, which is no surprise. So I have treated them with Quick Cure (1/2 dose as advised for puffers and also not daily as directed but every 3-4 days for 14 days), did a 30% water change today, vacuumed the gravel as well. I also treated with Maracyn.
My other concern is the GSP, his belly isn't fat and round like the Figure Eight's are, almost seems concave. I have watched him carefully and he is definitely eating well. I had several snails (20-30) in the tank ready for them once I got them home, the GSP went to quick work eating them up!
I have attached a couple of pictures, was wondering if he was just improperly cared for at LFS and just needs an appropriate diet or if he may be suffering from some internal parasites or perhaps something else....

Picture 25.jpg

Picture 26.jpg

So my questions are:
What's wrong with GSP?
Am I doing the proper treatment for Ick?
Can I should I continue with the Melafix/Pimafix, or will that just be med overload?

Info:
15 gal quarantine tank. It was fishless cycled a few months ago, had a few other guys in there before puffers, they showed no signed of any illness over the 2 weeks they were in there nor since they've been moved to their permanent homes, I did a 50% water change/gravel vacuum before putting puffers in. The LFS had them in freshwater with aquarium salt added, so I have done the same thing for them. 1 Tbs of salt per 2 gal. Intending on slowly introducing marine salt, until I reach 1.005.
Current parameters:
Nitrate: 0
Nitrite: 0
Ammonia: >0.25 ppm (almost impossible to tell with my kit as 0 and 0.25 are almost identical in colour, I'll take to LFS to retest) Should be ok as tank was fully cycled, unless I over cleaned it....
Alkalinity: 140 ppm
Ph: 7.8
Water Hardness: soft/slightly hard (140 ppm)
Water temp: 78°
Any help would be greatly appreciated. I know I shouldn't have bought the GSP, but he sort if picked me (may sound crazy, but I'm sure some of you know what I'm talking about).
Thanks in advance, and I wish my first post here was for another topic, but I'm sure me and my puffers will be showing up on this board a lot in the future.

[Pufferpunk]

If the fish you had in the QT did not carry the same amount of bioload of the fish in there now (puffers put out a LOT!), then the tank will not be able to support them, causing cycling problems in there. You could possibly add Tetra Safestart, which contains live, nitrifying bacteria but it may not be enough ever, to support that many puffers in a 15g. You should get a larger QT & do much larger WC (like 50-80%/day), to keep the ammonia/nitrate at 0. The fact that you don't have any nitrate is worrysome, as that means the BB isn't established.

Please read the many articles on these subjects (caring for GSPs/F8s & treating for ich), along with lots of other informative ones like, Feeding Your Puffers.

I'd do an 80% WC asap & add fresh carbon to your filtration to remove the ich med, as it can be extremely harmful to a puffer. The heat/salt/WC method stated in the article should work fine for your fellows, in addition to using the Mela/Pimafix for their fin issues.

[Babsrocks]

Thanks, I'll read the articles about the Ick, and do a water change/media change but I'm not sure ammonia is my problem. He was like that when I bought him (that's why I shouldn't have bought him).
And like I said, my ammonia card is very difficult to read as 0 and 0.25 are almost the same color. So it could very well be 0.....
It looks like this:

209_API_Ammonia_1.jpg

So I will go to LFS and have them test the ammonia.
I've heard many puffers are wild caught and often have parasites, could this be the case? All the other guys seem to be doing just fine, just some fin damage, but fat, round and happy.

[Pufferpunk]

Oh yeah, I forgot to mention reading the article in our Library about treating IPs. Good idea to have a 2nd test done at the LFS.

[Babsrocks]

Just a little update on my little guys.
They have been moved into my 55 gal tank and ate most of the million snails that were in there... lol Fat happy little campers now!
The 55 gal is a well established FW tank with an established bacterial colony, hopefully it can keep up with the puffers, but the filter I have in there is for up to 100 gal so it should do ok with the extra bio-load. All water parameters seem to be in check. I will continue to monitor to make sure it's keeping up.
GSP is doing well. He's definitely fat and round now, no sign of a concave anymore. One of the figure eights started to develop cloudy eyes, though this might have been a result of ammonia levels in old tank, so I am treating with Mela/pimafix, salt and heat. I've slowly brought the temp up to 85 degrees. Cloudy eye Figure Eight seems to be doing well otherwise, still active, swimming about hunting for his next meal. He seems to be seeing ok, very adept at finding hiding snails that blend into the rock formations. Hopefully with the ammonia level in check, he will recover.
So I hope with the parameters under control and hopefully proper treatment for the ailments, my puffers will be happy and healthy in their new home.
I have bought some instant ocean and will start slowly bringing up the salinity to brackish. Hopefully I do it slow enough as not to overly disturb the ecological balance in the tank. What is the best way of doing this? Increase weekly? With every WC? And how much per addition? I've never done salt water/brackish water before, so I just want to make sure i do this right. Any advice or experience would be appreciated. I tried to find an article, but was unsuccessful, perhaps my search terms weren't right. So if you know one exists, if you could point me in the right direction, that'd be appreciated too.
Thanks for your help so far!

[Pufferpunk]

Since the puffers sound like they are doing much better in the larger tank, I'm going to lock this thread. I think you need to post your last post in the BW forum.

[Babsrocks]

Thank you, have posted the question regarding fresh ----> brackish in BW forum.
Thanks for your help.