Corydoras

Question
-Hi!
I am new to fish-keeping, and I am starting out with a 20 gallon, corydoras
species tank.  I set up the tank, so there's gravel, fake plants and a couple of
decorations, and the filter and heater are running.  The temperature is at
74-75 F, (its a little hard to read) and I am doing a weekly 5% water change.  I
plan to start using my gravel vaccuum soon.  I have 2 emerald cories, each of
which are about an inch long, so they arent full grown.  I just got them about
4 days ago.  the first day or so, they were still a little freaked out, and were
swimming wildly over the tank, and not eating.  Into the 3rd day, though,
they started schooling more and sucking on the gravel.  I have tried putting in
algea pelets, (the brand is Hikari Tropical) but they have flat out ignored
them.  the flake food i am using is Nutrafin and they ignore while its on the
top, I assume thats because they are bottom feeders, and i think they eat it
after it floats down into the gravel.  I never see anything go into their mouths,
though.  
    I am worried because today they are kind of sluggish.  Not really
swimming very fast, and they are starting to just sit behind the plants and
chill.  Is it becasue they were really stressed the first few days and couldnt
sleep?  or are they sick?  I looked at them, and they dont have any fungus or
stuff like that.  their dorsal fins do look a little frayed, however.  When i
bought the tank, i asked the man who was helping me, (and who seemed
incredibly knowlagable) about an amonia testing kit, and he pretty much just
blew it off.  Said that the fish would cycle my tank for me, and i didnt need to
test pH or anything.  my dad, unfortunatly belived him, not me.  (I'm only a
teenager, but I researched this tank for three months before buying it, so I'm
not jsut guessing at this.)  Anyway, when i questioned this, he showed me a
testing kit, but it was 35 dollars, and my dad said if its not essential, Im not
paying.  I was told that the water comes out at about 7.6 where I live, and
decreases after you add living things.  Could this be what is making my fish
like this? Or are they only tired? My water is declorinated, by the way.  I really
dont want to lose these fish.  
Thank you in advance,
Betty S.

Answer
Hi Betty:  congratulations on the new tank and the cory cats.  They are great fish.  Do not be too worried that they are just hanging out... that is kind of what they do. They will be more active at night then they are in the day time.  I would feed them one algae wafer every other day and let them eat the flake food as they find it.  You can take your water to the local aquarium store and they should test it for you for free.  The frayed fins should get better as the fish settle into the tank.  I would not worry to much about this unless it gets worse.  You can also use aquarium salt as a preventative to most diseases in your tank.  I would change 10-15% of the water in the tank each week and make sure you use the gravel vacuum.  You will also want to keep a fish journal where you log in your maintenance and tank chemistry as well as what fish you add and when.  I hope this helps... and please ask me any other questions you may have.  dave