can i keep these fish

Question
QUESTION: Hi Lynda, hope this helps i have been feeding them blood worms and complete micro granuales for small tropical fish.How regularly should i be changing water with a 75lt tank WITH fin rot??i have a pair of nigrican ciclids and 1 electric yellow n a bristlenose.the nigricans were bitting the tails of the black widows so passed them on2 a friend.between the fin rot and tail biting i didnt think they would have much of a chance.

ANSWER: Hi Kaye,
I hate to tell you this but Nigrican Cichlids grow to 6 inches, and need a 50 gallon tank.  When kept in small tanks, their growth is stunted, their internal organs have no place to grow, and eventually they die.  When keeping Cichlids of this nature, we must have big tanks, rocky formations, and a PH of 7.6 to 8.5.  Your water temperature should be 78 degrees.  
If not kept in suitable tanks, they will get sick.  The African Cichlids, and Lake Victoria Cichlids are aggressive fish, and territorial.
Water changes of 25% should be made every week if your chemistry is right.  They should have zero ammonia, zero nitrites, and nitrates should be low.
If you are not considering buying a bigger tank, it would be best to bring them back to your Pet Store, and ask for a credit.  There are many little fish that would love a 15 gallon tank, and would be less trouble to keep.
I hope this helps
Lynda

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QUESTION: hi Lynda
thanku for getting back to me and for telling me that the Nigricans are not suitale for my 75lt tank.How ever i am wondering if i can keep a electric yellow cichlids and red zebras??if not are there any cichlids u could recommend??

Answer
Hi Kaye,
African Cichlids really need a bigger tank, as being very aggressive, and territorial, they need lots of hiding places with rocky formation.  This takes up lots of room.  The red zebra grow to 5 inches, so you must rule him out.  The Yellow Electric grows to 3 inches, and must be kept with 3 females, which would be too much for your size tank.  They are also good swimmers, and need lots of space to swim.  The only African Cichlids that you could keep in your tank are little shell dwellers.  You must provide shells for them as they are very fearful.  They race into their shell at the sound of noise, or even a shadow.  The shells must be 2 inches deep, and you must buy new shells when they get bigger.  They cannot live without their shells, they would die.  You have to make sure that the entrance to the shell is big enough for them to enter.  They need a sandy bottom, and 8.0 to 8.3PH  They are cute little fish, and they need a varied diet.  A good quality flake, bloodworms, and brine shrimp are a must to keep them healthy.  There are also special food for them at the Pet Store.  Vary their diet if you decide to buy some.
You could go with South American Cichlids who are less aggressive, but they too, are territorial, and need hiding places.  The Ram, is a beautiful little cichlid, and you could put 4 of them in your tank, but not with the Shell Dwellers as their water must be acidic.  6.5 to 6.8PH  This is very important if you would like to keep Rams.  You could mix them with small tetras, or swordtails, or platys.  They too need a varied diet to stay healthy.  Overturned pots, and hiding places are also a must, but you wouldn't need as many hiding places as you would need with African Cichlids.  You can buy little clay pots at your Dollar Store.  
It is very hard to keep Cichlids in small tanks.  It is up to you, and which ones you like best.  Also your water quality will play a role in this matter.  It is easy to achieve alkaline water, but to make it acidic, and soft, this is another matter.  If your tap water is neutral, then their is no problem, but if it is higher, there would be a problem to keep Rams.
4 Rams with a school of 8 small neon tetras would be enough for your tank....or 4 rams and 3 swordtails...or 4 rams and three platys.  The swordtails, and platys must have 2 females if you buy a male. It would be better to buy females, as males will harass the females.

African Cichlids, and South American Cichlids do not mix.  The African needs alkaline water, and the South American needs acidic to neutral water.  Although aggressive, the South American Cichlid is less aggressive than the Afican Cichlids.
I hope this helps
Lynda