New To This - But Had A Red Tailed Shark Die - Here's My Story...

[bryan1234]

Hello, totally new to hobby - had a little help from friends who have larger tanks - I bought a 20 gallon tank, not a tall one, standard wide one, with a bio wheel filter, set it up, had it cycle over a week, tested the water, water was perfect - I had three snails in it during the cycyling (two mystery, and a nerite) - then when the water seemed great, went to petsmart, originally got three tiger barbs (the glo version) - three hatchet fish - a clown pleco - and then I saw a really cool fish (red tailed shark) and noticed he was in a small tank with other community fish, then I asked the petsmart person about putting this red tailed shark in my tank (I know, I know, first mistake...) they said no problem he will only get around 4 inches.  Okay so fish go in (a couple days before shark died I added 2 more barbs and two more hatchet to make them five each so groups were bigger, recommended by one of my friends) - the shark died last night...but long story - the shark and fish started out great - he was territorial at first and undertandable - claimed my fake coral reef with caves as his own -so currently all the fish are great - the snails are vibrant - the couple of live plants look iffy - but like four days ago the shark started to look lazy and lethargic and was hanging out in cave, not coming out....and that got worse - ammonia was a little high at first but considered normal for a new tank, and it was getting better...and he died last night and I sort of feel bad - especially now that I was frantically doing research hours before his death and everyone is saying at least a 55 gallon tank for this little guy, then some said he was nocturnal and hiding is natural, so it was a little confusing - but after all my reading up on this type of fish I can conclude he got stressed and too much of a small environment I guess got him stressed and he did not adapt well...so...darn.
 
So my tank is at 91%, and the fish are all very happy and vibrant now like I said - I guess is it safe to replace the red tail with a safer alternative -I really liked the little guy since he was that one little cool different looking fish lurking around - any suggestions?  Or what I have is just fine - I'm happy with it, just missing that one unique guy that does his own thing - or if anyone has a general idea of what would be a final addition - thanks

 

[fatheadminnow]

Hello and welcome to the forum.
 
I'm going to "get on your case" a little here lol.  First of all, if the filter you installed was brand new, your tank was not cycled in a week.  It takes on average 4 - 6 weeks to properly cycle a tank.  
 
What test kit are you using?  Strip test kits are inaccurate.  Best test kits are liquid test kits.  I recommend the API fresh water master test kit.  You need to test for Ammonia, Nitrite and Nitrate.  "Perfect" water doesn't tell us much.  We need hard numbers.  What are the numbers for Ammonia, Nitrite and Nitrate?  
 
Since your tank was not cycled and you introduced fish, you went into what is called a fish-in cycle.  A place you really don't want to be.  Ammonia over 0.25ppm will cause gill damage to the fish and can kill them.  Nitrite over 0.25ppm will cause nerve damage and can kill them.  Keep these two parameters at 0ppm is very important.  This is obtained through a properly cycled and established tank.
 
Please read this article on how to properly do a fishless cycle:
 
http/www.fishforums.net/index.php?/topic/421488-cycling-your-new-fresh-water-tank-read-this-first/
 
Since you have fish in the tank you need to test ammonia and nitrite daily and do water changes to keep those parameters at or below 0.25ppm.  For example, if your ammonia is at 1ppm, you will need to do a 75% water change to drop that down to .25ppm.  This will more than likely go on for a few weeks if not a month or so.  
 
My suggestion is return the fish, or have someone, with an established tank, keep them in the mean time and do a proper fishless cycle.  Much less headache.
 
Hope this helps clear a few things up.   

 

[Byron]

Welcome to TFF.  Fatheadminnow has dealt with the cycling, so while we're waiting for those answers I will just comment on the fish species issues.
 
First, to confirm the tank size, this is a 20 gallon.  You refer to it as not a high one but a standard...the "high" 20 gallon is 24 inches in length, while the "long" is 30 inches in length and obviously shallower than the high.  Knowing which you have will help.
 
Second, as you now know (I assume), a red tail shark will not work in so small a tank, regardless.  This fish will grow to five inches, and it requires a 4-foot tank minimum.  And even then, it is not a community fish, no matter what Petsmart may say.  It cannot be combined with other substrate fish of similar shape, and beyond this it often takes a dislike to upper fish, especially those with stripes for some reason.  So I would forget this fish.
 
Barbs and hatchets are shoaling fish that therefore require a group, as you have been told.  However, barbs of any species are fairly active fish and more swimming space is better for them.  Also, the Tiger Barb (the "glo" version is the same species, so same behaviours) is a feisty fish and needs more in the group, say 8-10, but also a larger tank (30 gallon minimum for just this species on its own; larger if other species are included).  I would suggest you see if you can return these.  Aside from the numbers and tank size, there is a tendency for this fish to nip slower fish and hatchets will be prime targets.  You may not be seeing this yet, but assuming these fish settle in and behave normally, you almost certainly will see it, and that means the hatchets will be severely stressed and likely die.
 
I'm sorry to have relatively bad news, but these are things we all had to learn at the beginning, and we are here to help you--and your fish--avoid them.
 
Byron.

 

[fatheadminnow]

If you want, feel free to read the attached on setting up and cycling a tank.