I can't keep my fish alive!!

I definately haven't been keeping track of nitrates/nitrites, etc. I just recently bought a two mini kits - one for amonia and one for pH. I tested the water before I did the complete change and they both were normal readings according to what I researched online. Is there anything else I should be testing? I don't have tons of money to spend on kits- so what REALLY needs to be tested?

As far as water quality- I have well water and it never was a problem in the past with the tanks my dad used to keep.

What's bio spira?

Is the filter ok or should I get something else? (Penguin 100 w/ Biowheel)
Also- if I want to have planted plants do I have to have an undergravel filter?
 
The filter is good, bio spira is the only biological additive (but probably isn't needed in a 3 year old tank) wich actually works.

You do not need an undergravel filter in a planted tank, but, if your plants have roots that are planted in the substrate, you should have some form of water movement through the substrate(heating cables under the substrate is best IMO).

The bare minimum of test kits you need are: amonia, nitrite, nitrate and PH.
 
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