cause of death for electric yellow cichlid

Question
QUESTION: Hi Lynda,

I hope you are doing fine.I have a tank of about 30 Gallons and it houses about 5 pairs of African Malawi cichlids.Recently One of the electric yellows died yesterday and it has red scaled around its posterior towards the tail.I put it in a quarantine tank(bucket filled with a  pinch of salt),but it did not survive.It was showing signs of aloofness earlier but I did not bother much.
Few months back,I had few cichlids dying because of this red scale disease(thats when I upgraded my tank and got a big one).I do water changes in my small tank  (75% once in a month) and weekly,I clean the filter.
Also this time when I made 75% change,I have this feeling that I might have added more amount on first aid medicine.Could that be a  cause of death.Please advice.

The remaining fishes look allright as of now.But from my experience,I think this disease will migrate onto other fishes as well.

ANSWER: Hi Ashwin,
I would suspect that your water chemistry is not right.  Please check it to make sure.  Ammonia level must be zero, or safe, Nitrite level must be zero or safe, Nitrates should be low.  When the water chemistry is off, fish will get sick, and die.
Removing 75% of your water is a NO NO.  You must remove 25% of your water every week to make sure you water chemistry stays perfect.  Removing 75% of your water is not good because you are removing good bacteria which must stay in your water.  Once you have a cycled tank, you remove 25% of your water once a week.  Check your water frequently to always be sure your ammonia, nitrites, and nitrate levels are right.  If they are not, then disease sets in very quickly.  
I would also like to mention, when cleaning your filter, never rinse your sponge in hot or tap water.  Rinse it in water that you have removed from your tank.  A sponge is full of good bacteria that your fish need in order to survive.  If you rinse it in hot, or tap water, you will kill the good bacteria that is in your sponge.  A sponge is good for a very very long time, until it is old, ragged, and falling apart.
Adding medication to a tank that does not have good water chemistry will kill fish.  When you changed 75% of your water, your water chemistry changed, and adding medication surely killed your fish.
I also would like to mention that african cichlids need alkaline water.  Please check your PH also.
Write back to me once you have checked all four of these:  Ammonia, Nitrites, Nitrates, and PH.
You can buy these small kits at your pet store or walmart, and they should be number one in your fish cabinet.  They are always handy to have.
Lynda

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QUESTION: Thanks So much Lynda.I will definitely follow your advice of changing 25% water weekly.Also I used to clean the filter with salt water which my friend had advised,and clean it with the used tank water.By the way I am located in India(Bangalore),so no Walmart here and the fish stores generally don't keep the nitrate/ammonia checkers although I will try & surely find it out where I could obtain them.I dont want my remaining to die so will do anything to make them survive.
Today just before reading your message,I have made about 20% water change.I also put 2 drops of the medicine in it just to make sure it s free of worms/parasites to the water that I added.I hope it is fine.
So do u recommend adding medicine to the weekly water changes which I would make?

Once again,I really appreciate your reply.Looking forward to hear back from you.

ANSWER: Hello,
Having nothing to see if your water chemistry is good will be very difficult for you.  I hope you will somehow find these test kits.  They are so important.  Never add medication when medication is not needed, and especially not when you don't know if your water chemistry is right.  Adding medication, if your water has ammonia, or nitrites could kill off all your fish.
Your water should also be alkaline seeing as you are keeping African Cichlids.  To be on the safe side, buy crushed coral, or seashells, and wash them very well.  Put this in your tank.  It will make your water alkaline.  It is very hard for me to say how much crushed coral, or seashells you will need, but I would put in a big handful of crushed coral, and a few seashells. Keep doing little water changes of 10% everyday, this should help.   It would be very sad for you to lose all your fish, but if you do...start over, and let your tank run with nothing in it for one month.  Do not clean your filter, and leave the used sponge in it.  Seeing as you have a friend with an established tank, ask him to give you some of his gravel.  The gravel in an established tank is full of good bacteria, and this will help you cycle your tank.
For now, do not clean your filter, let it run for at least 3 weeks without cleaning it.  Good bacteria will build up, cycling your tank.
I hope all goes well for you, and that you don't lose anymore fish.  This is so heartbreaking, I know just how you feel.  Continue doing little water changes, add 6 teaspoons of diluted aquarium salt to your water.  This helps fish with stress, and parasites, but do not use any medication in the future.  You cannot cure fish if you have ammonia, or nitrites, and if your nitrates are high.  It is the ammonia, or nitrites that is causing them to be sick, and die.  Ammonia, and nitrites are the number one killer of fish, and the only way to help your fish is to get rid of these by cycling your water.
I hope all goes well for you.
Lynda

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QUESTION: Thanks again Linda.I will bear in mind not to add medicine unless really required.Now I see 3-4 fishes coming to the top and trying to breathe,not sure if they do it on routine.But they look active and few of them go down and again come back.I wanna know if these are signs for things to come.Any quick measures u suggest?
Today before reading your review,I made 25% water change and added 2 drops of medicine.Do you think I should replace 25% of water now and replace it with water with no medicine.
Also while making these water changes as suggested,do you think I should use a siphon to clean the gravel or just pure water change?

Answer
Hello,
Make sure there is enough oxygen in your tank.  The water from your filter should splash down to the water of your tank causing water movement for the fish to breathe.  Adding an air stone would also help.  The way you are describing them to me, makes me think they are lacking oxygen, so check this to be sure.  Too many big water changes is also not very good.  Two drops of medication should not be enough to actually hurt them, but do not add anymore.  The carbon in your filter should remove the medication.  When you make your 10% water changes, siphon from the bottom.  You do not want decaying food in your tank.  Do these water changes for one week, and hopefully things will get better.
Keep me posted on how they are doing.
Lynda