My fishes

Question
Hi ,

My tank is 2.5 feet long and 1 feet wide, I have 5 goldfish, 2 shark catfish, 2 sucker catfish, 4 karps, 1 guppy, 1 tiger barb, 2 platies, 1 swordtail, 2 gouramis . There are 20 fishes. It is a normal filter. I donot know the ph level.I change it everyday ,1 gallon. I am trying to sex a platy and a swordtail and accomplished my mission. Now i want to spawn my gouramis . How do i know which is male and which is female. Is there a problem in building nestswith a uncalm water.Please answer my questions . Do i have to keep them in a special container.

with kindness,
Niraj

Answer
Hi Niraj;

I hate to be the bearer of bad news but the tank is too crowded to breed egglayers such as gouramis. Your livebearing platies and swords will breed no matter what but all the others (egglayers) need more space and privacy to spawn. There are just far too many fish in that size tank and you have coldwater fish mixed with warm water tropicals too. Most of the fish you have, especially your goldfish and carp are going to eat any babies and eggs that appear, as well as  seriously stress out the fish that may try to breed. What your fish will need are separate spawning and breeding tanks, each with it's own species so they can have the space and privacy they need to concentrate on laying and fertilizing eggs. Here is information on sexing and breeding gouramis;

http://freshaquarium.about.com/cs/anabantids1/a/gouramicare.htm

http://az.essortment.com/breedinggourami_rdks.htm

http://www.aquaticcommunity.com/gourami/breeding2.php

Good luck...

At Your Service;
Chris Robbins