betta listless since purchase and after medication

Question
Dear Lynda,

Hi! I just want to thank you for all the advice you've given me these past few weeks and to say that unfortunately Davey died three days ago. It was really sudden; on thursday I got up to feed him and he didn't greet me, he was floating by the filter and was breathing very hard, his gills and mouth were openening and closing at the same time while he was barely keeping himself at the surface. At one point he was floating head down. I did a 50% water change on the vague possibility that it was ammonia, but his behavior didn't change. He also refused to eat. I had to go to work and got home at round 10 so I couldn't check on him but by the next morning he was dead. I did an ammonia test and there was nothing so I can only assume his mystery illness finally got the best of him. needless to say I'm devastated and I just want to thank you for the support you gave me during his illness and I have a few last questions to ask regarding disinfection of the tank because I'm a little unsure of how well I went through with it.
I've completely torn the tank down, I soaked each piece of equipment including the tank itself in a diluted bleach solution (9 parts water 1 part bleach) for 10 minutes and right now I'm letting everything air dry. I threw out the filter insert, ceramic media and sponge cover and replaced them with new ones but I'm wondering whether you think I should keep the gravel. I did the same bleach soak as above on the gravel, but it's giving off a slightly rotten smell. Should I just buy a new bag of gravel?
Also, I really want to keep my live plants, (they're in a bucket of fresh dechlorinated water with fertilizers added right now since the tank is still drying) will a gentle bleach dip eliminate the pathogens? (I've read 19 parts water 1 part bleach followed by a 1-2 minute leaf soak and a quick dip for the roots) One last thing, the anubias plant is attached to a piece of driftwood, can I soak the whole thing or will the driftwood absorb the bleach and leach it out later?
I'm going to be waiting until the tank re-cycles before I get another betta, which actually shouldn't be that long since the seachem stability did wonders these past few days. My only overall concern is whether the bleach will be gone by the time the tank's ready. Have you ever bleached your tanks(s)?

Thanks so much,
emilie

Answer
Hi Emilie,
You are very welcome, and I am so sorry you lost your little pet.
 If your gravel has a bad smell, I would just buy another bag, but if you have lots of gravel, then I would say clean it in bleach, but rinse it out again, and again to get the bleach completely out.
 I would not soak a piece of driftwood in bleach.  
 
To answer your question, yes I have disinfected a tank with bleach, a long time ago.  It was a 75 gallon tank.  I washed everything with bleach, but rinsed my gravel really well, emptied the tank, filled it up, and emptied it again, and again.  I was lucky, I had many friends at the time with tanks, and I had lots of tanks too, so filled it up with water from my other tanks, and friends were bringing buckets of water from there tank...oh it was a job, and I will never forget it!!  lol
When you fill your tank, add water conditioner, it will help get rid of any trace of bleach that would be left.   Also bleach evaporates over time.  
I am not a plant expert, so I would not chance to tell you anything on plants.  We have an expert on the team who would help you much more than I can.
Make sure your water chemistry is right before adding your new friend.  Zero ammonia, zero nitrites, and nitrates should be low.
Have a nice day
Lynda