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On the inner walls of my glass 29G, theres a tough coating of dirt like substance that is extremely hard to get off the glass. It is also on plastic parts such as my filter.

mainly, it forms where the water line of the tank is, and parts of the tank where it is constantly being wet and dried over and over again. when the "dirt" is wet, it almost appears to be clear, but when it is dry, it turns white.

I tried soaking the plastic pieces in bleach, and i scrubbed them like crazy. Its very cloudy and makes the appearance of the tank look unhealhty.

Does anybody know what I'm talking about? Could this be calcium deposits in the water that are left behind when the water dries up? how do i get rid of it?!

Sounds like mineral deposits. which tend to be an unavoidable fact of life if you live in a hard water area.

First thing to do: get a hardness test kit and test the hardness of your tap water (or whatever water source you're using to fill your aquarium. Draw off, say, 2 litres, then leave the water to stand for about 12 hours in an inert plastic container, then test it. You can find a conversion table for water hardness values in a range of units here and take note of the values at the bottom that determine the difference between soft and hard water as measured in °dH ...

Once you've ascertained how hard your water supply is, this will give you some angle on the appearance of mineral deposits in the aquarium. Even in an area whose water supply has a relatively low mineral content, it's possible for deposits to build up over time, but if you live in a hard water area (particularly if the water is hard enough to make keeping Rift Lake Cichlids your safest bet because your water is like liquid rock, as one other poster here described his supply) then a deposit of this kind can form quickly.

Since a good percentage of the deposit will consist of carbonate minerals, the quickest way to get rid of them is a mildly acidic solution. Bleach won't work because it's alkaline, and may paradoxically make things worse. An acid, on the other hand, will react with the carbonate minerals and convert them to a possibly soluble form. However, you need to exercise care with your choice of acid - vinegar is probably about as strong an acid as you can use even in small quantities anywhere near live fishes, and even then only with caution. In a stripped aquarium with no occupants, you could of course let loose with nitric acid, which would eliminate the deposits in seconds, but under NO circumstances should you let fly with even dilute solutions of nitric acid in an occupied aquarium, let alone fuming nitric acid that I used to use during my chemistry lessons at school!

Usually, mineral encrustations are carbonate salts of calcium and magnesium. If you use something like citric acid from lemons to remove them (which should be safe to use in the proximity of your fish), then they should be removable with ease.


Panda Catfish fan and keeper/breeder since Christmas 2002

Awesome.

That was a fantastic post. A+.

Tomorrow I will grab one of the plastic pieces off of my filter and soak it in a bucket with some vinegar and lemon juice for a while.

hopefully if this works, i will transfer my fish to a different tank while i let loose with a vinegar/lemon mixture, rinse everything, and throw in some new water with some water stabilizer and dechlorinator.

Appreciate the help!

On the tank glass, you can also raise the water level so it is soaked and softened a bit and then use a razor blade to scrape it off. I've also used something abrasive, like a handful of fine sand or a plastic scouring sponge, but they have potential to cause small scratches on plastics so be very careful. It does let you avoid moving fish/plants/substrate around though.

Acid is your best bet, as above You really do want to rinse well when you are done though, as leftover vinegar can upset your pH.

For animals, the entire universe has been neatly divided into things to (a) mate with, (b) eat, (c) run away from, and (d) rocks. - Terry Pratchett

....once you've actually cleaned up the exisiting deposit using the great advice posted, my advice to you is give it a good cleaning everytime you do a water change - this prevents it building up over time and turning into a huge job every few months

I have hard water and it affects both my 14 gallon acrylic tank and my 73 G glass tank.

With each change I pop the hood/canopy off and use the condensation on the glass and a good dish cloth (no longer used on dishes!) and scrub away the deposits. I have nto had to use any acids to get rid of them as its always just started to form so it doesn't take much effort to get rid of it.

Also - I steer away from scowering pads etc - especially on the acrylic tank as it caused a bunch of tiny scratch marks on the tank (which i a pissed about). So instead, I use a plastic squeegy/scraper on it (mostly for green spot algae though). Works much better.

You know what they say - a stitch in time saves nine.



72G Bowfront. 1 Sunshine Peacock, 2 Yellow Labs, 1 Ps. Elongatus, 1 Blue Ahli, 1 Red Kadanga, 1 Mel. Exasperatus, 1 metriaclima emmiltos, 1 Ancistrus.

14.5G 4 Neon Tetras.