hard water, lime or calcium buildup in aquarium

[David D]

Anyone have any success cleaning up hard water buildup in an old aquarium, bought an older tank with alot of build up, I tried laying the tank on its side and soaking with vinegar, and scraping with a razor scraper, it removed some, but the tank still shows cloudy stains on the glass from the buildup with water in it, most is around the top waterline area, any suggestions would be appreciated. I'm thinking of using CLR next but the chemicals may be harder to remove from the tank than the buildup. Is it possible i'm just too impatient and need to work the vinager soak longer and multiple times?

[Tuscany Heather]

I’ve used CLR to remove hard water deposits in a shower. I’ve tried many things and that is the only thing that I find works. However, I have no idea if would be safe to use for fish after it’s used. Good luck. 

[Wrencher_Scott]

On 7/27/2022 at 4:36 PM, David D said:

Anyone have any success cleaning up hard water buildup in an old aquarium, bought an older tank with alot of build up, I tried laying the tank on its side and soaking with vinegar, and scraping with a razor scraper, it removed some, but the tank still shows cloudy stains on the glass from the buildup with water in it, most is around the top waterline area, any suggestions would be appreciated. I'm thinking of using CLR next but the chemicals may be harder to remove from the tank than the buildup. Is it possible i'm just too impatient and need to work the vinager soak longer and multiple times?

It sure wouldn't hurt to let the vinegar soak for a long time. I would say patience is very important.

I have seen windows so bad nothing would remove the stains. It was as if the glass was etched or something. 

Good thing is it will be less noticeable when it's filled with water.

 

[nabokovfan87]

On 7/27/2022 at 4:36 PM, David D said:

Anyone have any success cleaning up hard water buildup in an old aquarium, bought an older tank with alot of build up, I tried laying the tank on its side and soaking with vinegar, and scraping with a razor scraper, it removed some, but the tank still shows cloudy stains on the glass from the buildup with water in it, most is around the top waterline area, any suggestions would be appreciated. I'm thinking of using CLR next but the chemicals may be harder to remove from the tank than the buildup. Is it possible i'm just too impatient and need to work the vinager soak longer and multiple times?

Empty tank, I would just fill it with vinegar, diluted, and then let it sit.  I've also seen people take vinegar on a more difficult area and soak a paper towel and let that sit on the affected area with a paper towel for a few hours.  Flip aquatics has a video on one and the dude from BRS (sorry, I just don't remember his name) on his old channel.  I'll try to grab those for you.

As far as day-to-day and how you maintain a tank with hard water, the biggest issue is the rim, lid, filter, and any cables.  It creeps up on you, can block out light, and using something like an airstone makes the situation exponentially worse because you're tossing that stuff everywhere in those regions. 

Once a month, whenever I get annoyed by it, I'll go ahead and do a deep clean in a sink.  I use a sponge and clean the plastics, paper towels (only with water) on the rim/tank itself, and then scrap any glass with a razor or use the sponge and hot water to clean it.  No soaps, no chemicals, no nothing.

Here is the new tank filled with diluted vinegar.
 

Here is the other method.
 

 

[Brandon p]

On 7/27/2022 at 7:36 PM, David D said:

Anyone have any success cleaning up hard water buildup in an old aquarium, bought an older tank with alot of build up, I tried laying the tank on its side and soaking with vinegar, and scraping with a razor scraper, it removed some, but the tank still shows cloudy stains on the glass from the buildup with water in it, most is around the top waterline area, any suggestions would be appreciated. I'm thinking of using CLR next but the chemicals may be harder to remove from the tank than the buildup. Is it possible i'm just too impatient and need to work the vinager soak longer and multiple times?

It is very hard. I buy used tanks to breed because of this fact. It depends on how long the tanks were like that. The hard water can get into the microscopic dimples in the glass. Once it’s in those it’s almost impossible to get out. I have tried everything. Thank normally why you can get glass tanks cheap. Try to talk to a glass glazer. They have some tricks but most don’t know about. Clr is fine to use just rinse well.

[quikv6]

You can also use Bar Keepers Friend, and rinse well.

[Guppysnail]

Not that is helps you get away from vinegar but it shortens the time I have to soak my glass lids by a little due to my liquid rock water. I use cleaning vinegar at 6% acidity vs standard distilled at 5 %. 

[Minanora]

My 75 gallon tank was a used turtle tank. I should have taken before and after photos. Anyway, I used a utility blade lubricated with water for the really bad stuff then used a towel with hydrochloric acid to soak off the rest. A 9.5% solution was needed to get it off. I know that's extreme but it saved many hours of time.

If you use an acid be sure to wear the appropriate PPE. Chemical gloves, eye protection, and do the work outside not on the grass though.

I've used cleaning vinegar as well on lesser buildup but it was not nearly as effective for my 75.