sulfa smellmilky water

Question
We have a 72 gallon tank that has been in use for about 5 weeks - we had only four baby ciclids in the tank.  at the time we added the baby ciclids the water tested practicaly perfect according to the readings.  about a week after we put the four fish in the water turned like milk.  it has been about three weeks and now the water is much clearer but not as clear as it was before we added the babies.  we have just added more ciclids to the tank and all are doing quite well.  now, we have a sulfa smell.  we do use a product that removes ammonia, nitrates and nitrites - could that be the cause of the smell?  the product does have an odor.  we have changed the carbon that we put into the sump of our wet/dry filter and seems to have helped.  what could be the cause of the smell and what do you think the cause of the milky water was?  thank you for your time and help.

Answer
Hi Mary Ann:  I would do a 30% water change and make sure the gravel in the tank is really clean... sounds to me like the tank is trying to cycle again... you can add bacteria to the tank if you'd like... but I would go to the aquarium and ask them for some "dirty" water... its old water out of a sponge filter... would work well in jump starting the bacteria.  Keep my posted.... I would also add some active carbon to my filter... if that is possible... dave