neon tetra

Question
i have 7 neon tetras 1 peppered catfish a bristlenose catfish 6 cherry shrimps and about 6 or 10 guppies and 2 bala/silver sharks and a white/gold shark in this tank they are all under 5cm long i was told some of the guppies were Mollies but i cant tell them apart i have 5 questions and they are

1. how do you tell the difference between guppies an Mollies?
2. will the neons breed in this tank it is a 2ft tank running at 24c-26c and pH sitting at 7.20 as read on the digital pH reader

3. if not what can i do to change it so the neons breed i have another 2ft tank standing by if i need to change them into that one with different pH and temps

4. i have my red tailed black shark in the standby tank cause he was chasing my bala sharks and making them scared like them twitching and not moving around the tank so i removed the redtailed shark and now there back 2 normal Why is this shark bulling the bala sharks?
5. is it normal for the white shark to hide under wood and things an only swimming at night or when the light around the tank is very dull

PS sorry about the amount of questions i would appreciate your ideas and knowledge on these matters thank you for reading this and answering

Answer
Hi Ben,
 1. Mollies are substantially larger than guppies.

 2&3. As far as I know, no one has ever bred neon tetras in captivity, and not for lack of trying.  Some fish do not breed in captivity and neons are one of them.  It is possible that they need to be in very large numbers to spawn.  

 4. All fish can be territorial.  One fish chasing another is normal.

 5. I suspect that someone is bothering the white shark and that is why it is hiding.

-- Ron
  rcoleman@cichlidresearch.com
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