Well, nice to see that people are finally getting note on this breed of fish. They truly are magnificent. To give you a bit of information on them, they originated in Thailand and Singapore. They are extremely aggressive fish with absolutely no fear of anything. They are usually greyish black with green an dblue however they ado have a silver color that looks pure white, not very rare either. They are live bearers. The tank should be as large as possible with the length being much more important than the depth. The rest of the tank can be planted anyway you like but some of the plants around the edges should reach the surface. The addition of some floating plants will also help mimic it's natural habitat. Leave some open space areas for swimming. Not the easiest fish to care for, they require the addition of some sea salt to maintain their best health. Provide gentle filtration with a slight water currant. . They will accept flake and frozen food, but they will fare better with live insects like mosquito larvae, fruit flies and daphinia. The addition of a supplement containing vitamin D and A is an absolute necessity if you wish to breed them. Care must be taken when they are first introduced to the aquarium, if they get startled and dash about they may injure their lower jaw and this will lead to certain death. During spawning the male will swim up to the female and nudge her sides with his beak. He will keep this up until she accepts him. The gestation period is also quite long and can last up to eight weeks. The broods are generally small. The newly born fry can be fed almost immediately on the finest flake food or baby Brine shrimp. At birth the upper and lower jaws are the same length which develop as the fry mature.
The blye water is because of the vitamins and small amount of sea salt in the water. These fish usually live in shallower water so the surface is where they spend most of their time anyhow, not too worried about that, but that one that doesn't stay on the top I would have some slight concern for. They are a member of the Hemirhamphidae family, they are commonly known as wrestling half beaks. They can be adjusted to flakes but only high quality will keep them alive long, so like I already mentioned it is important to get them live food. They aren't picky with live food, but they need it. Oh let's see what else. They are very very aggressive fish. A lot of people think Betta's are aggressive well these will without a doubt win a fight over a betta. They are known to fight to death, they stab each other with those sharp bottom jaws. They will eat their young, they will kill another fish and pick at them, most of the time fight each other over the dead fish. Your gourami's I suggest you get another tank for, ro else get the half beaks another tank because within a month, you will have nothign for fish left. They will kill anythign that you put in with them. The Celebes half beaks you can find info using the scientific name Nomorhamphus. However, I don't like using that name because it gives very little on the fish. here is a nice link, it is a pay link but you can find out lots about them through this place if you really want to.
http://www.livebearers.org/ Not all that great of a site, but they got info on your fish. A few quick stats for you as well...
size: 2¾ in (7 cm)
tank: 32 inches
strata: top
pH: 7.0 to 8.0
Hardness: medium hard to hard
temperature: 68ºF to 82ºF
I have also included a picture of the silvers and the tris-