Identifying Disease Questionnaire

As a beginner, novice, or experienced fish keeper, there is a very good chance that you are going to come across some form of disease, parasite, illness, or irrational behaviour in your tank. Regardless of where you fit in the scale, at some point in time, you will need assistance in identifying the problem, finding a solution, and more importantly, know how to prevent it from happening again.
I have seen many people throw in the hobby completely because of not knowing what to do, or by getting poor advice from a Local Pet Store. By doing some Internet searches, a lot of people get directed to TASA, and I believe this is an excellent tool to introduce new members to the forum. So if you are new to TASA, and have a disease, or problem, welcome, and keep reading.
The main purpose of this thread is to assist you in correctly identifying the problem. In many instances, by the time we have ascertained enough information to help correctly identify the problem, it is either too late, or too far down the line to cure. So I have compiled a whole lot of questions for you to copy-and-paste into a new thread, fill it in, and then we can more than likely assist you within a few hours.

I am a firm believer that 90% of diseases are owner caused, and can be reduced by simply following 2 practices. (1) Maintain your weekly water changes, monthly filter clean, and general maintenance of the tank, and (2) Quarantine all new fish and plants before introducing them to an already established tank. You will find a wealth of information on these basic principles on this forum, so I am not going to expand on them at all.

Firstly, resist the urge to just throw in medication or salt. A lot of the fish supplier companies have come up with products like “Heal all” and “General Tonic”, and claim that these medications will cure a whole bunch of illnesses. Whilst this will work wonders on an illness that it does cure, you will only be prolonging the problem if the medication is not intended for your problem. The problem is that you may dose with an “all purpose” medication, and then find out later that your medication will not cure symptom X. You then need to add Activated Carbon to the tank, ideally do a water change, and let the Activated Carbon remove the “all purpose” medication for a period of 24-48 hours before you can administer the correct medication. The process of doing a water change, or fiddling with the filter to add the Activated Carbon will stress out the fish further, and obviously the delay of 24-48 hours will further cause problems. Rather take an hour to fill in this form, and wait a few hours to get the right answer. I can almost guarantee you that you will have some expert advice within 8 hours of posting your thread... we are just that good on TASA. Mixing medications is a definite no-no. If you have one medication in the tank, I always advice that the medication be completely removed before adding any new medication. I personally wiped out my ENTIRE 300 litre aquarium (Fish + plants) in a matter of 10 minutes after adding 2 differing medications.

So without delay, here is your homework: (Some of the questions may seem odd to you, however they all play a critical role for the TASA members to get a holistic interpretation of your tank, so please answer as much as you can, with as much detail!)

General
Where do you stay?
How long have you been keeping tropical fishes?
How long has the tank been running before you added fish/this fish?
What fish do you have in your Tank (type, number and size)?
When did you last buy any new fish?
Which food are you feeding and how often do you feed?


Disease
Describe the problem that the fish is having (behaviour, breathing, excretion (droppings), food intake, colour)?
Is the fish eating?
Has the problem occurred before?:
Have you treated the problem and how?
Have you had any other problems in the past?
What were they?
Did you treat for these problems?
How?

Your aquarium & Maintenance
How big is the tank. (L x b x h)?
How many litres of water?
What type of filter do you run?
What is IN the filter?
How many litres per hour is the filter rated for?
How often do you clean your tank?
How do you clean your tank?
How much water do you take out for Water change?
Do you prepare your water for water changes? How and what do you add?
What water do you use. (Tap, bore hole, RO)?
What substrate do you have?
What else is in the tank (Rocks, plants, fake plants, shells, anything else)?

Water parameters in your aquarium
Describe the water (smell and colour)?
Temperature of the water?
General hardness (GH)?
Carbonate hardness (KH)?
Ammonia:
Nitrite (No2-)?
Nitrate (No3-)?
pH?
How did you test these? Have you checked the expiry date on the test kits?

Lights
What light do you have?
How long is the light on for?
Do you have lots of plants in the tank (real or fake)?
How do you fertilize the plants?

If possible, can you post some pictures of
(1) The sick fish
(2) A close up of the sick fish, and/or effected area
(3) the full tank.

This questionnaire has been compiled by an original questionnaire from Dirk Bellstedt (which can be found here). Questions from the Original have been expanded on, and certain questions have been added.