Tankmates for Red-tailed shark

Question
QUESTION: I have a 30 gallon tank tha Sadly now only contains a red-tailed Shark, A cory cat, and a chinese algea eater.  I lost 2 keyhole Cichlids and 2 Angels to an ammonia spike over a couple of nights.  I now have the tanks chemistry under control and hte other fish seem to be doing fine.  We learned the hard way about letting my kids overfeed these guys.  My question is this; what are some good tank mates for the shark?  My wife wants a Betta and I am considering many of the tetras for the tank. we also are considering a loach, but do not know which species would be right.  You adivec on this is appreciated, thank you.

ANSWER: Hi Jerry,
Unfortunately Red Sharks should be kept alone.  They are aggressive, territorial, and as they get bigger, they will terrorize a tank. There are no exceptions to the rule.  A Betta would be stressed, get sick, and be killed by a red tail shark.  Tetras would not survive.  It is also sad to keep one cory cat in a tank.  They love to play, and live in groups of 6 or more.  They are a schooling fish.
You either must get rid of your red tail shark, and buy other fish, or keep him alone.  If you decide to keep him, please return the little cory.
This is the sad truth on the Red Tail Shark.  Beautiful fish, but cannot be mixed with other fish.
Lynda

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QUESTION: Ok then, Consider the same set up with out the shark.  I do planon adding some albino corys.  the cory I have is a spotted, will he school with the albinos?  Would any of the tetras be compatible with the betta. What species of loach, if any,might work in this tank?  Also, and this is a longshot, My oldest child (5yrs) really wants a blood red parrot cichlid for some reason.  would one of these fit in with the rest I have mentioned?  thanks for your time and Help.

ANSWER: All little cory fish  get along, and school together.  They make good tank mates for the betta.  A school of neon tetras, or cardinal tetras do get along with Bettas, and you could put 8 in your tank or more.  You could also add 3 platies, one male, and two females or three females, or white cloud minnows, rasboras, one drawf pleco ( You must feed the pleco, and the corys with algae pellets that you find especially made for them.  They also like sinking shrimp pellets.)  I am mentioning this as people think that bottom fish eat what other fish leave behind.  This is not true, they do not eat rotting food, and must be fed, or they will starve to death.
Each Betta has a different character, much like people, some are more aggressive than others, but they usually do well with small schooling fish as mentioned above.  You must keep your water free of ammonia, nitrites, and nitrates should be safe at all times.  Water changes of 25% every week using a good water conditioner is a must.
Be careful not to overfeed.  A betta should have a varied diet in order to get all the vitamins he needs, and should be fed twice a day in small quantities.  Example:  2 pellets for one meal, or 2 flakes for one meal.  We must be very careful when feeding bettas as their tummies are the size of their eye.  Food that bettas should have are Betta Pellets, Betta Flakes, Daphnia, Glassworms, Plankton Flakes, Mealworms, and Bloodworms.  Vary as much as possible.  Feed him one cooked frozen pea with the outer layer removed, and cut into little pieces once a week.  On the day you feed him the pea, feed him nothing else.  This is very important, as bettas are prone to constipation, and constipation goes unnoticed, and leads to Swim Bladder Disease.  He must clean out his system.  Your other fish can go without food for one day, it is only good for them.
The Blood Parrot is a No No.  They do not mix with Bettas, they get quite big, and need a 50 gallon tank.  
With Bettas, we must always be careful what we mix them with.  Their long skirt is an attraction to all fish, which is why it is better to keep him with small schooling fish so that he won't be stressed, and nipped.
Kuhli loaches should be okay, buy two as they too need company.
Add silk plants, to your tank, so that all the fish feel secure.

Hope this helps.
Lynda

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QUESTION: Thanks again for all your help. it has been invaluable.  In the 30 gallon tank would it be ok to keep both a male and a female betta or should I stick with the one male?  Also doyou know anything about Ghost Glass Catfish?  specifically will they live well witht the tetras and betta?

Answer
Female Bettas are just as aggressive as the male, therefore should not be kept together in a tank.  They are very good at finding each other, and then the male or female would kill.  Even when spawning them, one must not take there eyes off them during the spawn.  At any moment, the male can turn on the female with intent to kill.
Ghost Glass Catfish are very peaceful, and should be kept in groups of 6 or more.  The more the better.  The Betta should get along with them.  I say "should," because each betta has his own character, some are more aggressive than others.  Some Bettas have been picked on too.
I would also recommend that you put the betta in last.
Also do not add all of these fish at once to your tank.  Your chemistry would change, killing off all your fish.  Go slowly, very slowly.  Buy two little catfish, and wait 5 days.  Check your water chemistry, if it is perfect, add two more, and wait 5 days again, and so on.  With neons, because they are small, you may add 4, and wait 5 days, check your water, add two more neons, and 2 other fish that you intend of putting in.  Do water changes every week, and before buying fish.
Never keep the Glass catfish alone, they must be at least 6 or they will die.
  Guppies, and mollies do not mix the betta either.  The Guppy being mistaken for a Betta, in the Betta's eyes, and mollies do nip, and need alkaline water.  I just thought I would mention this, as many vendors sell them with Bettas, and then trouble starts in your tank.
Lynda