pleco

as said already .5 ammonia is your problem. Do the water change, and monitor ammonia especially over the next couple of days.

Try and work out why the ammonia went up.

A common pleco would get far too large in due course for a 30 gallon in any event and is a messy fish - what size is he now and do you have adequate filtration.
 
as said already .5 ammonia is your problem. Do the water change, and monitor ammonia especially over the next couple of days.

Try and work out why the ammonia went up.

A common pleco would get far too large in due course for a 30 gallon in any event and is a messy fish - what size is he now and do you have adequate filtration.

i would say 7.5 inchs and yes i have a good filter
 
that is the problem. that fish is just to much bioload for the tank. you are going to keep having ammoina problems, which are going to get more severe because he is going to get bigger, if you dont get him a larger tank or take him to an LFS.

wats a LFS
 
When you say you clean the tank every other week, and do a water change every week, what do you mean by 'clean the tank'? You don't want to take everything out and clean it, or you'll never get enough good bacteria to get rid of your ammonia.

How is the pleco doing now?
 
When you say you clean the tank every other week, and do a water change every week, what do you mean by 'clean the tank'? You don't want to take everything out and clean it, or you'll never get enough good bacteria to get rid of your ammonia.

How is the pleco doing now?

i mean that i use a vaccum with a tube and clean the fish crap from the bottm of the tank and hes seems to be doing better is sitting on the bottom with his stomach down but he doesnt want to eat when i fed my fish today but i hope he gets better
 
I would be doing at least 30% changes weekly. What do you mean when you say you replace the filter every 3 weeks? What kind of filter do you use?
 
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