Alright, where to begin...
On the discussion of proper volume to comfortably accommodate Carinotetraodon travancoricus, many debates provide good points. In my own experience, I've successfully kept (and occasionally bred) a pair of dwarves in a 5.5g growout for over a year now, to great avail. They're quite fat, seemingly content, and amiable with each other. I keep their tank very heavily planted with all of the clippings from my other ten or so aquariums and the little guys help me prevent the spread of snails between my tanks. In addition to copious pond, micro-ram, and Malaysian trumpet snails, they get to snack upon the population of cherry shrimp that I released in there. I also employ one ottocinclus along with three yamato-numaebi that have yet to display any signs of stress or injury.
My success likely comes from several factors:
1: The numerous bunches of plants (anything from HC to Najas guadalupensis) help to break up the line of sight and allow the puffers (along with the other inhabitants) to find refuge from one-another. This helps them to feel secure, and thereby decreases their stress and aggression. In addition, the constant addition and removal of plants aids in inhibiting their tendencies to establish territories, thereby deterring their natural instinct to defend their "home."
2: I make certain that they are well fed. I put in large pond snails (which are too big and hard to be bothered by the puffers) so that I never find myself without a source of eggs. This keeps many snails of varying size within the range of the fish, so they can graze whenever they feel hungry. Additionally, the juvenile cherry shrimp (and, occasionally, the adults) provide an alternate food source. I also toss in blood worms if I have extras after feeding my gobies. This provides them with a wide range and variety of food, so they donít resort to eating each-other. In my experience, a happy puffer is a full puffer.
3: I use a filter rated for a 20g aquarium, resulting in a 5x turnover rate in one hour. Travancoricus really are messy eaters, and nothing will hurt your efforts worse than shoddy water quality. That means that weekly water changes are a must. I also have 54 watts of lighting over that aquarium (using diy CO2,) which gives me about 10 wpg (give or take.) My plants pearl like crazy, grow rapidly, and act as a nutrient sponge, keeping my water parameters pristine. This brings me to my next point:
The plants you provided wonít help you. Primarily, the concept of avoiding cycling by employing plants is based upon the assumption that you are providing a high-tech system. Usually, weíre expected to provide 2-4wpg, along with CO2 and macro/micro nutrients. Now, keep in mind, high tech doesnít have to mean high budget- I simply use desk lamps with screw-in CF, $2 diy CO2, and a $15 filter, along with dry ferts for a pittance. Itís a little harder to upgrade the lighting on an Eclipse, but if youíre so inclined, (and diy handy,) you can manage it.
The plants you chose were also slow growers. This makes them great for a low tech, low maintenance aquarium, but they wonít be able to utilize the excess nutrients in your aquarium quickly enough. You need stem plants like Rotalia indica, Hygrophila difformis, etc that will grow rapidly and eliminate dangerous chemicals. Typically, 10-12 stems per 5 gallons is safe, so youíre looking at 30-45 stems. The items you provided to help seed your aquarium may help, but without a source of sufficient chemicals (ie more fish,) your bacteria levels wonít be very high, so itís a moot point.
Anyway, interpret my information as you would. If you plant your aquarium heavily (as in more than just a handful of plants,) provide an abundant food source, add only 2-3 puffers, and keep a vigilant eye on all of your inhabitants, you should be able to do well. You should carefully consider your situation, and decide if a low or high tech aquarium would better suite you. Lastly, you should relax and have fun with this- aquariums are supposed to help us unwind, not cause aneurisms.
Well, I apologize for the rather lengthy post, but I hope it helps. Good luck, and keep us posted!!!