ammochips work
Ammo Chips do work, but there are a few things that might be helpful to remember. I wouldn't just dump them in your tank; they won't really work properly just sitting at the bottom, not to mention it'll become a pain trying to get them all out.
For ammo chips to work properly, there needs to be current running through them to circulate ammonia through the resin of the ammo chips.(ammo chips are basically rocks that have been coated with a chemical resin that dissolves, removing ammoia.)
One way to do this is to get one of those small, mesh filter media bags (found in the filter section of your aquarium store) and put the chips in that. Then, place the bag of chips (about four tablespoons) directly into your filter reservoir. This will force water through the chips, providing the needed current.
But an even better way is to use a bubble current. Using bubbles to dissolve filter media is most always more effective than water current. There is a product that is made by the same folks that make ammo chips that is a prepackaged "ammo chip holder", if you will, that is designed to hook to an air hose. You place this small contraption in a bottom corner of the tank, and air bubbles rise up through the ammo chip holder, providing eccellent circulation. It's not exactly beautiful to look at, but it the most effective way, plus the added airation from the bubbles is great for hatching fry.
CAUTION! Do not use ammo chips for an extended period of time! I take it that you know all about cycling a tank and all about the biological filter (though it does concern me that you have no gravel in your tank for bacteria to colonize). Remember that the micro organisms that are essential for removing ammonia AND OTHER TOXINS from your tank feed on ammonia and oxygen. If they do not get these, they will die, resulting in what is called a "bio crash." If you leave your ammo chip filter in your tank long enough, all the ammonia is removed and the bacteria will die. This is bad, and will kill your fish. I learnded this lesson the hard way, as a few months ago, I left my chip filter in for about four weeks, and I had a bio crash, and all of my fish died--a very expensive mistake. I have had to start my tank over, but I still use my chip filter every now and then when ammonia levels get so high that water changes don't work. Ammo chips should only be used occasionally to remove exess amounts of ammonia. If you have cycled a tank properly, ammonia should be filtered out naturally, and you should only need ammo chips to help control the occasional surge in ammonia level.
I hope this information is helpful. Yes, I use ammo chips, and am very pleased with the results. Also remember that they go bad after about two weeks and you'll need to replace them, or recharge them by soaking them in a saltwater solution. (see ammo chip carton for directions). Also, if you have any questions about cycling your tank, let me know by posting a reply to your thread, and I'll be happy to expound on that topic.
Good Luck,
-valjeangotback
