which fish to start with?

Question
QUESTION: We purchased a 40 gallon tank and are in the process of starting the tank.  Our pet store suggested after running the tank for ~5 days that we start with 5 tiger barbs, and they are in and looking good 1 week into this process.  It seems there is so much conflicting information about when it is safe to start adding other fish to our tank.  I am also interested in what varieties will be interesting and 'hearty' as we are new to this hobby.  There seems to be an incredible amount of conflicting information out there, and I am having difficulty sorting through it.  Question 1:  when can I start adding others and at what rate?  Question 2:  could you recommend specific fish and quantities that will make an interesting, healthy tank.  (my son wants bala sharks, so I am particularily interested in what would work with these).  Thank you.

ANSWER: Hi Kim,
I think you are doing really good so far. The thing you must keep in mind is you need to cycle your tank first with the tiger barbs before you add anymore fish. Adding more fish too soon can cause ammonia spikes and sometimes total tank wipe-outs, let alone disease risks.

So what I would do now is to cycle your tank first. Which basicallys means---leave the tiger barbs in the tank and let everything run for at least 4-6 weeks. *Test your water everyday  for ammonia for the first several days and then its best to test for ammonia, nitrite, and nitrate. This is so you can determine if you tiger barbs are safe and also how far along your tank is in cycling. Testing your water also enables you to know when your tank is ready for more fish.
For a while ammonia levels may rise and fall and soon Nitrite will appear and ammonia levels may drop a bit while nitrites may spike. Sooner or later Nitrate appears as the bacteria get established. Whenever your ammonia and nitrite levels drop to Zero consistently, it means your bacteria have established enough to keep the ammonia under control and it is -safe- to add a few more fish per week (about 3-4 small fish per week works well) You must be sure to test your water the day after adding each new addition(s) just to make sure you don't get any kind of ammonia spike due to the new bioload on the tank. If this happens, a quick 50% water change should fix an ammonia spike and soon the bacteria should take over and deal with the ammonia and drop it back down to zero.

~The most important things to remember are-
*Wait until your ammonia and nitrite levels are ZERO first
*Only add a few fish per week
*Test your water the day after adding the new additions
*Make those vital water changes when needed
*Have plenty of patience and stock your tank gradually.

Tiger barbs should get along great with most other community fish like Tetras, other barb species, Rasboras, Livebearers,  Catfish, Loaches, Danios, plecos ect.. Just make sure no fancy-finned fish because as you know, Tiger barbs are well-known fin-nippers.

Bala sharks are awesome fish. But they can grow to large sizes of up to 10" and they are active fish that enjoy being in small groups. Now a small group (maybe 4) of Bala sharks would be fine in a 40-gallon for a good while. But as they got larger they would really be best in something like a 75-gallon and up. Preferably a 6-foot tank if you really want to keep them happy longterm.

The fish selection is up to you but I think the five tiger barbs is a good starting point for building up a community tank. I think at least one other schooling fish would be good. These could be danios, tetras, rasboras, or other barbs. Make sure you have a group of at least 6 or more of any schooling fish species.
Some kind of bottom feeder like Corydoras catfish are great. Avoid common plecos. They are the most popular algae eaters but their drawback is the huge size they attain of 12".
The best pleco is Bristlenose plecos. They are neat little catfish, just like a regular pleco but they only mature to about 4 inches or so. But algae eaters are not vital in everytank. If you maintain the tank properly, you won't have algae problems.

A few livebearers would really bring some color and activity to the tank. Platies are very vibrant colored and hardy fish. Plus, like with other livebearers, they have live babies about once a month, but other community fish usually eat the fry. Platies thrive best in large groups. 7-8 would be really colorful. One livebearer that can cause trouble are Mollies. Avoid these fish for now. They demand really good water quality and they are often suceptible to illnesses that other fish aren't even bothered by.
Fancy guppies might be out of the list of possible fish because the tiger barbs might nip their fins.
Swordtails are similar to platies and they should also be compatible with tiger barbs.
So there are also other schooling fish like Zebra danios, Leopard Danios, Giant danios, which are all very fast, non-stop swimming little fish. They enjoy being in groups of 6 preferably at least 8 to enjoy their grouping behavior.

Rasboras such as the Scissor-tail Rasbora and Harlequin Rasboras would be an interesting contrast to your Tiger barbs. Both fish are reasonably hardy as long as the tank is cycled.

All the tetras that are available like Neons, Cardinals, Red-nose tetras, Glowlights, Head-and-tail light tetras, Silver-tip tetras, Lemon Tetras, ect...

Other barbs are very suitable as tankmates for tigers. Gold barbs, Rosy barbs, Cherry barbs, Black Ruby barbs and Checkerboard barbs are all good tankmates for tiger barbs. Just make sure to keep these fish in a group.

I really hope this helps you out with your aquarium. Just remember to stock your tank slowly, gradually building up any schools of fish.

If you need anymore help, let me know!
Karen~

---------- FOLLOW-UP ----------

QUESTION: Karen,
Thank you so very much for the great advice.  Here is my problem of the day.  This morning one of the barbs was dead.  I did a test strip and was at the 'stressed' level on the strip.  I did a 50% water change.  Within 2 hours the other 4 were dead as well.  Please tell me:  Do I let the tank cycle as is?  Do I add one or 2 fish (barbs again or danios?) for a couple weeks, was 5 too many for 40 gallons?  Even though I changed 50%, the ammonia level still reads 'stressed' on the test strip; do I exchange more water, or leave it as is?  I very much appreciate your time as we are true novices and want to do this right.

Answer
Hi Kim,
Sorry to hear about the fish trouble. The problem may have been that you caught the ammonia spike too late and the fish were already too stressed. Or maybe the water change wasn't enough. Sometimes ammonia can be at such a concentration that even a 50% may not be enough. Something else you have to consider is some tap water companies have chloramine as well as chlorine in their tap water. Many water conditioners break the chloramine bond but that means that it leaves ammonia free in the water. So when doing water changes you can deliberately adding ammonia to your tank.

These are all things to consider when you have such bad fish loss. I sure hope it doesn't happen again. Something bad probably just happened with the water quality.

you might want to consider fishless cycling instead, that way you'd avoid the terrible problems that can come with cycling with fish. here is an excellent how-to here:
http://www.aquatic-hobbyist.com/profiles/misc/fishlesscycling.html

And don't forget sometimes water conditioners and ammonia neutralizers will produce false readings on your test kit. Make sure to double check with this also.

I hope this helps
Best wishes,
Karen~