Betta Fish Died

http://www.petforumz.com/betta-died-ftopict46198.html (betta died and now what?)
So, unfortunately my little betta died, after the long battle with what i thought was flex. I still want to keep bettas so i was wondering how i should clean the tank to prevent this from happenin..
« Do a search for cleaning agents at http://www.thatpetplace.com for freshwater fish tanks/equipment. Sorry everyone for posting a lot of that pet .. »
« in article batik RemoveThis @batik.com says... What I have always done is fill the tank 1/3 or 1/2 with a 20% bleach and water. Put the filter into.. »
« Just to add one more thing. Many common bacteria, like the flavobactium, are present in most (or all) commercial aquariums anyway. You may.. »

http://www.petforumz.com/male-betta-died-ftopict43456.html (male betta died)
had him and a female in a 10 gal. for about 6 weeks. yesterday he started looking lethargic and this morning just kinda drifted off and died. everything for the tank is normal except that the temper..
« sounds like it could be an oxygenation problem in the water....just a guess though from the behaviour. »
« Sounds like a natural death. Presuming that there were no obvious signs of disease or damage. Your danios are active so that sort of says .. »
« "Jim Brown": The I fish yes, the danio's are quite active. one of the frogs had recently (within the last week) shed his skin. the wife is.. »

http://www.petforumz.com/bowl-gravel-cleaning-fish-dies-ftopict52692.html (bowl, gravel cleaning after fish dies)
I had a betta fish and it died. I want to get another but know I must clean the bowl and gravel before putting a new one in it. What is the best way to clean these so they are free of anything..
« I just wipe it out with a paper towel and water. if a disease killed the fish then the fish was already sick with the disease, it was mor.. »
« a little bleach. rinse a lot and then put it out in the sun for a day. be sure to use dechlor in the water. ingrid Nicki Sinclair: ~~~~.. »