Do you need to disinfect tank that held sick fish?

BichirMohawk

Jack Dempsey
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Oct 7, 2016
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A fish with dropsy died in my 20 gallon tank about 6 months to a year ago. I emptied the tank right after the fish's death. The tank's been sitting in my garage and has dried up a long time ago. Do I need to disinfect the sand and tank to use right now? If so, how would I disinfect the sand?
 

skjl47

Goliath Tigerfish
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May 16, 2011
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Fill it up with water(almost) pour bleach in it. Run it with the bleach. Stir up the sand.
Hello; This.
So I don't need to disinfect it?
Hello; To each his/her own but I clean and disinfect most tanks as a matter of course. A tank that sit around empty can pick up stuff as well.
While I would use a bleach solution soak for the tank and any equipment there is another method that does two jobs. Most used tanks have some needed cleanup. After getting all the substrate out and giving a good rinse I usually make up a salt paste.
Ordinary table salt with a bit of water can make a paste. I use a soft cloth or such to wipe the inside of the glass with the paste. Most stuff on the glass will come away and the salt does not scratch the glass.
I then let the salt dry to a haze. My guess is the salt paste will dry out most critters. I then do a final rinse and a test fill.
Do what makes you comfortable but I have disinfected tanks, substrate and equipment with bleach. It is simple and effective. Keep in mind you will need to dose the tank with PRIME or some such after.
 

duanes

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Certain infectious bacteria have the ability to sit dormant for months, even years, add water and they come back.
It is true that many bacteria are ubiquitous and are useless to try and disinfect out, Aeromonas, and viruses like Lymph are always present, waiting for lowered resistance in fish.
Some phages however, are problematic and should be disinfected out.
How was the diagnosis of dropsy made?
Was a lab test done to certain it really was Aeromonas?
If it was something else (and I say this because many pathogenic fish bacteria show similar symptoms) I might not take the chance, of not disinfecting.
If it were say, columnaris, I would disinfect before using the tank, and substrate again, because columnaris can sit dormant in old dirt, and reinfect, wiping out a tank.
Since the substrate is dry, it will need to be cycled to get the good bacteria back anyway.
You have nothing to lose by disinfecting except time, and the cost of a dechlorinator after its done.
And the gain will be a pathogenic bacteria free tank.
 

skjl47

Goliath Tigerfish
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May 16, 2011
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Hello; I went back to a saved post of mine about sealing a tank in which I described how I clean a tank with salt. I use salt for run of the mill cleaning, tanks not known to have disease or parasite issues, and have for a few decades.
"I usually give a tank a good cleaning before applying the new silicone. I use a paste made from ordinary table salt (Without iodine) and a soft sponge. (note- It seems the iodine is not an issue, at least according to some. So iodized salt should be OK but I have not as yet use it.)
-(I do not use a sponge or cloth that has been used with soap or chemicals.)

-(I have buckets and sponges that are used only for my tanks.)

The salt paste does not scratch glass and does a fair job at removing the deposits from the surface of the glass (be sure the sponge or cloth used to apply the paste with is not coarse enough to scratch the glass on its own and watch for bits of gravel that seem to jump into the salt paste.) (Letting the salt paste dry to a haze should desiccate most critters if you want to disinfect a diseased tank.)(Note- wetting the glass will soften up the deposits somewhat.) Rinse the salt paste out and let the tank dry well before applying silicone."

For a tank with a known or suspected disease/parasite I have used a Clorox bleach solution. A few years ago I had cyanobacteria algae (slime algae) in all my tanks. I knew that erythromycin would only stop it short term and it is costly to treat a large tank or several tanks. There is also the possibility of creating a resistant strain of bacteria with too much use.
As I had live plants in al my tanks I needed to treat them also. I treated one tank at a time. I put the fish in a clean tank and the plants in a 5 gallon bucket. I treated the plants with a dose of erythromycin which was small for a 5 gallon bucket and was able to keep them in this solution long enough. Some have used dips for disinfecting plants but I have not yet.
I cleaned each tank and then filled with water and put some Clorox in the full tank. Let it sit for a day. At the same time I put all equipment in buckets of Clorox.
I rinsed the gravel well and when rinsed enough put it several 5 gallon buckets with water and Clorox. Even when I poured off the solution and filled and poured off each bucket more than once the Clorox residue remained in the gravel. So when I set a tank back up and had it filled and all equipment operating I then dosed with PRIME (SAFE works as likely will other such water treatment stuff.) Then it was cycling the first tank.
After getting the first tank cycled doing the rest was quicker. In the end and with some precautions I have been slime algae free for over three years now.
A lot of work and time spent but had to be done.
 
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