The rainbow sharks blackish-green body is accented by colorful reddish-orange fins. Also known as the Red-finned Shark, or Ruby Shark, this fish is primarily a bottom, and mid-level dweller. They're happy eating most anything. Spinach, lettuce, tubifex worms, algae, and leftover fish food, make them happy.

The Rainbow Shark is a semi-aggressive fish, which can also be very territorial. It's suggested you have just one in the tank, and fish in similar size. Also, it's best to avoid combining the Rainbow Shark with other freshwater sharks, such as the Red-Tailed Shark and Black Shark. Here are a few more characteristics to consider:

• Grows to 6 inches
• Tank parameters: 73-80 F; pH 6.5-7.5; KH 10-15
• Minimum tank size is 30 gallons; 50 gallons preferred
• Requires moderate care
• The rainbow shark is an Omnivore

Rainbow sharks are compatible with most barbs, danios, loaches, plecostomus, and the gourami. You just have to make sure and leave them space to establish a territory.

Breeding the rainbow shark in an aquarium setting isn't done due to the sharks aggressive behavior. If you've got the room in your fish tank, and proper companions, the rainbow shark can be a fun fish to keep.

FunFishTank: How long have you been breeding the swordtail?

"We've had the sword tails for two months. There are two
males and two females. This is my second group of swordtail fry. The first were
born right after we got the parents and we didn't have a
chance to isolate the mother. Most were eaten by other
fish, and we've had no luck with a breeder *net* -- all of
our guppy fry and our remaining sword fry died in the net,
so we decided to get the breeder box as a replacement."

You can see the fry in the plastic breeder box.

FunFishTank: How could you tell when the female was pregnant? How many fry did she have?

"We could tell the mother was pregnant by the dark triangle
in her abdomen. The swordtails are translucent fish and you
can see eggs and then eyes as the fry form. The swordtails had 9 fry this time."

The "dark triangle" Ian refers to is the gravid spot.

FunFishTank: What did you feed the fry?

"We feed them Hikari "First Bites" fry food. It sinks slowly
and the fry love it."

Check out this one day old swordtail fry! It's 7mm (.28 inches).

FunFishTank: What type of aquarium setup did you use to breed the Swordtail? Were their any other fish in the tank?

"Our tank is a 50-gallon freshwater tank. There are 4
swordtails, 4 white cloud mountain tetras, 1 cardinal tetra,
2 zebra danios, 2 leopard danios. There was one black molly
until very recently, and we plan on adding more mollies
soon."

FunFishTank: I've heard that the female swordfish can sometimes die after having the fry. Was your female ok?

"The female looked pretty stressed when we put her in the
plastic breeder isolation box. The box was underwater
(about 1 inch), so I had to feed the mom using a tube from
a ball-point pen. I put the tube into the hole at the top
of the box and dumped some flakes into the tube. The flakes
would sink slowly and she was much happier when fed. She was
fine after having the fry."

FunFishTank: That's good to hear! You've taken some great pictures. Could you tell us how you did it?

"I took the pictures using a Nikon D50 digital SLR camera
and a 50mm Nikkor macro lens. I set the ISO to 800 (I
think) and used a wireless, off-camera flash on its
lowest-power setting. I placed the flash off to the side
with a diffuser so it would light up the box but not blind
or scare the fish."

Thanks for sharing your experience of Swordtail breeding Ian! The two tips about using a plastic breeder box, and feeding the female are good to know.

Many popular Swordtails (Xiphophorus helleri) found in pet stores are hybrids, and come in assorted colors. Marigold, Black Nubian, Pineapple, Neon , Red Wag, and Red Velvet Swortails, are just a few commonly found varieties of this species. You might think the name comes from the sword shaped caudal fin protruding off the lower end of the male. Actually, the swordtail name is derived from the male's anal fin. You can determine the sex of the fish though, by the "sword" shaped fin. Male swordtails have one. Females don't. Notice the lack of this on the female swordtail in the picture. If you're interested in stocking the swordtail in your communty fish tank, keep the following in mind:

• Minimum tank size is 20 gallons.
• Tank Parameters: 65-82 degrees F; pH 7.0-8.2; KH 12-28.
• Swordtails are Omnivores.
• Peaceful fish perfect for community tanks.
• Grow to 4" in length.
• Easy to care for.

As live-bearing fish, the aquarium hobbyist can try their hand at raising fry. You can learn more about swordtail breeding here. These fish are able to reproduce in high numbers. Unfortunately, in the wild, they have become a nuisance in some countries where they were introduced to an area not indigineous to the species.

I've had the swordtail fish in my own aquariums. They are very pleasant, and swim quietly around. You could easily keep them with the Guppy, Dwarf Gourami, and I have even stocked them with Tiger Barbs.

Changing the cartridges looks simple. There's no need to empty out the water, which saves time. The aquarium bowl is actually ten times stronger than a regular goldfish bowl. But I still don't suggest dropping it!

In the base there's an air pump and filter hidden away. A light in the lid to illuminates your fish, but you have to buy the biOrb heater seperately.

So is it really that good? I read through some of the reviews of the BiOrb Aquarium, and one thing was agreed upon. This fish tank is not good for goldfish. They're just too dirty for it. This would make a great aquarium for smaller fish, such as neon tetras.

It was also suggested that the larger 16 gallon BiOrb aquarium was easier to maintain than the 8 gallon. Personally, I change the water in my betta bowls every two to three weeks, and do a monthly water change in the eclipse aquarium. The betta bowls only have a few gallons of water in them, and stay clean. I'd guess a 16 gallon tank like this wouldn't take any more work than a regular 20 gallon aquarium. It would definitely take up less space.

You can get the full specs on the BiOrb Aquarium here, or baby biorb here.

Also known as the millionfish or fancy Guppy, these fish are an excellent addition to the non-aggressive community fish tank. Special breeding programs have produced unique color strains in the species. Native to Trinidad, and regions of South America, the fish was discovered in Trinidad in 1866 by Robert John Lechmere Guppy. Although he wasn't the first to write about this species, the name "Guppy" stuck. Here's a few characteristics and items to think about when purchasing Guppies:

• Minimum tank size 20 gallons.
• Easy to care for.
• Grows to 2 - 2.5 inches.
• 65-81 degrees F, ph 5.5-8.0, KH 10-30
• Come in many beautiful colors.
• Guppies are live-bearers.

Usually you can distinguish the difference between Guppy males and females by coloration, and fin formation. Generally, the males are smaller, yet have brighter colors than the females. Also, female guppies have a rounded anal fin, and a pregnancy patch located near the bottom portion of their body.

Because these fish are live-bearers, you can have fun breeding them in your aquarium. Be warned though, if you try Guppy breeding, adults will eat the fry if they're left alone. You'll want to set your fish tank up specifically for breeding, if you're going to attempt raising them. This requires an environment with floating ferns and a breeding box which will protect the fry.

I have never tried Guppy breeding, but have friends that have raised fry. If you decide to try it, get ready to have a large amount of guppies to take care of. You'll want to make sure you have prepared a home for them. A pregnant Guppy can drop as many as 200 fry.

First, it will help to explain what cycling your tank actually is. Fish waste is fully of deadly ammonia. Fortunately, bacteria grow that eat the ammonia, and turn it into nitrite. This bacteria is called Nitrosomonas. It grows within a matter of days in the proper conditions, and eliminates the ammonia from your aquarium. It's waste product, nitrite, is also deadly to fish though. Another bacteria comes along, Nitrobacter, and eats the nitrite. Nitrobacter produces a waste product, nitrate. In small quantities, nitrate is safe for your fish. So instead of slowly building up these good bacteria by slowly introducing fish, fishless cycling prepares the aquarium for many fish at once. Benefits include:

• Less stress on your fish.
• Fish are never exposed to deadly ammonia and nitrite.
• Ability to add many fish at once. (I've added 7 neon tetras, and 2 gouramis at once. The gouramis don't view the tetras as food, because they were all added when small in size.)
• Fishless cycling is closer to a "natural environment" than adding fish to plain dechlorinated water.

So how do you do fishless cycling?

You add pure ammonia to your aquarium before adding fish. Now this method requires the same amount of patience as cycling your tank with fish. It took 4 weeks for me to cycle my 37 gallon eclipse aquarium. The nice thing was that I didn't lose a single fish, when I put them in all at once!

I'm not a scientist, nor do I play one on tv, but here's how I perform fishless cycling for a freshwater aquarium. I use ammonium chloride NH4CL, which I bought at a local store that sells chemistry supplies. You want to be careful about adding ammonia you find in some stores. They may contain perfume, or other unwanted additives.

First, I spike the ammonia level in my fish tank by adding the ammonia. You want it to reach 1 - 2ppm. It took 15 drops in my 37 gallon Eclipse tank to get the spike I needed. Test ammonia levels, and nitrite levels daily, before adding ammonia. I used a water testing kit.

I kept adding 15 drops, once a day. On the fourth day, I checked my ammonia level before adding any drops. The test was showing no ammonia was present. The Nitrosomonas bacteria was growing, and doing it's job. I had been checking nitrite levels every time too, and saw an expected nitrite spike.

Cut the drops you use daily, in half, when the nitrite spikes. In my case, I went to 7 drops a day. After 4 weeks of adding 7 drops daily, enough Nitrobacter had grown. Ammonia and nitrite levels were 0.

At this point you'll want to do a water change. Empty half the aquarium, and add dechlorinated water. The reason for this, is you want to clear an excess of nitrates that have formed. Add ammonia for a day or two more, to make sure ammonia, and nitrite levels are ok.

Add as many fish as you want, based on the 1 inch of fish/gallon method. Remember to add compatible fish. Then enjoy watching fish that are safe from deadly ammonia and nitrite, because you used the fishless cycling method.

I've seen pieces of aquarium driftwood in the local fish store, but I'd recommend checking out eBay for some really great finds and deals. I bought two pieces of driftwood that somebody had taken from the Ohio River. So what do you look for when you're purchasing driftwood for your fish tank? Number one, make sure that it's safe to use in an aquatic environment. Some driftwood sold for reptiles may be dangerous, and contain harmful chemicals that would kill your fish.

The next step, is to plan how many pieces of driftwood you'll need for your aquarium. I like to take out a pen and paper when I'm planning my fish tank layout, and draw some ideas. I'll also emphasize that sometimes less is better. I usually will use only two to three pieces of wood. It depends on the size of the tank. If your fish tank is large enough, think about getting a piece of driftwood that's large enough to act as a centerpiece for your aquarium. Then add a few smaller pieces around it. I bought a piece of driftwood that actually doesn't sink, and I wedged it into my tank higher up. The fish really enjoy swimming around it. Check it out in this video.

Usually the driftwood you buy commercially is clean. If it isn't, you want to use a brush to scrub any dirt or loose material off of it. Of course, never use any soap, detergents, or cleaning materials on a piece of fish decoration that will be placed in your aquarium. You want happy fish; not dead fish.It's best to waterlog your driftwood before placing it in your tank. Soaking the driftwood, for a period of one to two weeks, will allow any tannins that may be in the wood to release. Change your water if it becomes murky and be sure to use dechlorinated water for the procedure.

For small pieces of aquarium driftwood I recommend boiling them. Boiling in hot water for around 2 hours will not only sterilize your driftwood, but releases those tannins, that may be present.

Be sure your water level is low enough to fit the new decorations in your tank. Refer to your plan for placement, and arrange accordingly. Your fish should start exploring their new environment soon after!

Fish of the Tetra Species are ideal in a non-aggressive community aquarium, where you have some extra space, and want to add some fish with color. The bright striping of the Neon Tetra, and Black Neon Tetra is an eye catcher. I'd recommend them for anyone beginning a fish tank.