how to clean used/old fish tanks?

[solRNY]

hi,

i recently aquired some old/used tanks, was wondering whats the best way to clean these?

thanks,
-lang

 

[dreaminmel]

I hose them out in the driveway, mix up some vinegar & water in a spray bottle, spray down the tank, use razor blade where needed and then hose out again in driveway. If there's nothing that needs to be scraped, then a quick wipedown would work fine.

 

[Flanders]

I usually scrub with vinegar and then noniodized salt. where'd you hit this jackpot? keep me in mind if you have any extras you won't be using.

 

[NirvanaFan]

I usually do the same as mel. If something is really covered in coraline, you could always lay the tank on it's side and let it soak in the vinegar for awhile. You can only do one side at a time like this, but it will save some work.

 

[solRNY]

thanks mel, and flanders for the advice for a moment there i was thinking of filling each tank full with water/vinger and letting it sit for like a week, thats lots of water to dump into my lawn

flanders, there is a particular tank that needs work that i might not want to do, maybe you would, i will keep you in mind

 

[solRNY]

I usually do the same as mel. If something is really covered in coraline, you could always lay the tank on it's side and let it soak in the vinegar for awhile. You can only do one side at a time like this, but it will save some work.

haha, thats great idea! think i will do this for the one particular tank i will use for RO/DI storage

 

[downset]

Muriatic acid

 

[dreaminmel]

That won't damage the silicone at all?

 

[solRNY]

so i am going to to use muriatic acid instead of vinegar becuase i am impatient... dumping this stuff on my lawn will kill it? should i nuetralize it with some of baking soda?

 

[reefman5511]

Use the acid with plenty of ventilation since it does have some nasty fumes.
The acid will kill your lawn. Definitely neutralize it. Dilute it with water first before using the baking soda.

 

[Srixon]

Muriatic acid

That won't damage the silicone at all?

I use this all the time and have never had an issue....just remember that it is a strong acid and caution should be used when using it.

 

[solRNY]

thank all for the advices and caution, going to go with the "safer" labled muriatic acid, and try to be extra careful,

at first i just wanted to only clean the tanks, but i thinking i can acid clean the rocks that i been collecting inside these tanks as well

 

[Conesus_Kid]

Remember: Add acid to water when diluting, not the other way around!

 

[der_wille_zur_macht]

thinking i can acid clean the rocks that i been collecting inside these tanks as well

If, by "rocks" you mean typical live rock - wet or dry - the acid will dissolve it! Use at a very low concentration and test on a small piece first.

 

[tmz]

Muriatic acid is the cheapest and easiest. Put the tank outside fill it with water add the acid. I used a quart of so for a 55 g tank . Let it sit overnight . Dump it and hose it out. You may need to add more acid than I used depending on the crud in the tank. No it wont hurt silicone. Careful , don't splash yourself with the acid it will burn you. All it does is drop the ph to a point where the calcium carbonate dissolves.

 

[tmz]

PS: if you are worried about the acidity of the water when you are done you can add some clcium hydroxide( kalk) , sodium hydroxide(lye) or baked baking soda ( carbonate) or even unbaked baking soda (bicarbonate)to neutralize it.

The calcium carbonate rocks may have organics and precipitants. I clean them with a bath in bleach at about 50% plain Chlorox and water for about 2hours, followed by a rinse with fresh water.This destroys the organics by oxidizing them.
Then an acid bath( muriatic acid at roughly 1 part to ten parts fresh water)for a couple of hours. The acid bath will dissolve calcium carbonate as Willie noted. It ewill also neutralize the oxidants left over from the bleach bath. In effect ithe acid dissolves the top layer of live rock which is mainly calcium carbonate . A rinse removes the dissolved material and everything it may hold including metals like copper and PO4 sticking to the rock. Dry it out and you have clean dry rock.

 

[solRNY]

Remember: Add acid to water when diluting, not the other way around!

Thanks for the reminder

If, by "rocks" you mean typical live rock - wet or dry - the acid will dissolve it! Use at a very low concentration and test on a small piece first.

Thanks for the advice, going to try 10:1, if not strong enough then 5:1, this acid stuff sorta scares me! u got me thinking, I have more than just rocks, some sorta branching stuff, like dead corals... Acid bath them as well?

Muriatic acid is the cheapest and easiest. Put the tank outside fill it with water add the acid. I used a quart of so for a 55 g tank . Let it sit overnight . Dump it and hose it out. You may need to add more acid than I used depending on the crud in the tank. No it wont hurt silicone. Careful , don't splash yourself with the acid it will burn you. All it does is drop the ph to a point where the calcium carbonate dissolves.

Thanks for the details TMZ, i have the tanks setup in the garage so I am concern with the fumes, I will leave the garage door open for several hours after pouring in the acid, is this when its most dangerous? What happens when I shut the garage at night?

PS: if you are worried about the acidity of the water when you are done you can add some clcium hydroxide( kalk) , sodium hydroxide(lye) or baked baking soda ( carbonate) or even unbaked baking soda (bicarbonate)to neutralize it.

The calcium carbonate rocks may have organics and precipitants. I clean them with a bath in bleach at about 50% plain Chlorox and water for about 2hours, followed by a rinse with fresh water.This destroys the organics by oxidizing them.
Then an acid bath( muriatic acid at roughly 1 part to ten parts fresh water)for a couple of hours. The acid bath will dissolve calcium carbonate as Willie noted. It ewill also neutralize the oxidants left over from the bleach bath. In effect ithe acid dissolves the top layer of live rock which is mainly calcium carbonate . A rinse removes the dissolved material and everything it may hold including metals like copper and PO4 sticking to the rock. Dry it out and you have clean dry rock.

oh this is getting good, I will do the 50% bleach bath then the acid bath

Thanks for your advice guys/gals, as this allows us to continue our build and perpare the rocks

 

[solRNY]

update on our adventure with acid

so we ended up using the "safer" muriatic acid to start and observe what this stuff does,
we also filled two buckets, one with just fresh water and the other with lots of baking soda water in case of emergencies,
working with this stuff gives me the false sense that something is always burning,

one of the tank to be cleaned, seem like this thread is becoming more of a rock cleaning thread instead

this is after the 1st gal of muriatic acid was added, after adding the 2nd gal it started to bubble and foam a lot! did not notice fumes to irratate much,

after the bubbling has died down much, we decided that it wasnt enough, so we added a 3rd gal of the "non-safe" version, this seems to be much more potent, and much more fumes!

becuase we did not know how to use this acid we added each gal in steps, thus the ratio of 10:1 or near was never achieved,
next time well probably add all 3 gal at the same time to have a better cleaning,

learned to never pour the acid directly over the rocks, as i found it pretty much melted some larger pieces,

also learned when a power head is pointed at a rock it will make a big hole in it!

 

[solRNY]

some pic of what we cleaned,

 

[solRNY]

this muriatic acid is dangerous, take precuation! going to clean our skimmer