Are these limestones?

Dec 31, 2020
Hello guys. I'm setting up a 50 gallon aquarium that reflect the local landscape (I live in the UAE, where there are tons of limestones and granites along the hajjar mountains, from my understanding these are mostly sedimentary rocks). I've found a few good stones here (in the pic) in my last hiking trip.


In the vinegar (6% acid) test on them, there was some fizz but only minor and in corrosive areas. There is a common talk among aquarium folks that limestones leach heavy metals and alter PH/Hardness of the water. These usually come from people who aren't really geologists - I was looking for some reliable info on how likely the water (my tap water ph is 7.6-7.8, water hardness 4.0 dgH, carbonate hardness 4.0 dkH) will undergo changes? I do understand it may happen given the aqaurium water ph can fluctuate slightly but shouldn't this take a very, very long time? I would highly appreciate any expert advice on this.
Different species of fish require different pH levels. This is why it is so important to do some research before adding your fish. It is also important to make sure that you know the pH basics, before you add your fish to the aquarium.

The pH of water is rated on a scale of 0 to 14. A pH value of 7 is considered to be neutral. If you have a pH level below 7, then your water is considered acidic, whereas a pH value above 7 is considered to alkaline.

Aquarium pH level: Logan Price

Not maintaining the correct pH levels in water will cause your fish to become stressed out and they will eventually die.

Fill a bucket with some tap water, add an air stone, let the bucket set for 24 hours, and then test the pH levels.

Let the bucket set for another 48 hours and retest the pH levels again. The purpose of the air stone is to oxygenate the water. We understand that not everybody will want to or can do this but this is the safest way.

You’re going to need an effective way to test the pH of your water, so the product we recommend having handy is the master test kit from API. You can pick them up from Chewy for less than $20 and they will be your go-to kit for testing not only tap water, but your tank water for pH, nitrates, ammonia and a few other important pieces of information.

The reason you need to let the bucket set for 24 to 48 hours is because the Carbon Dioxide in the water causes the pH levels to drop. We highly recommend you buy a test kit for accurate readings of your water parameters, not only will this benefit your fish but it will also help your bank balance by not having to replace dead fish! Yes look after your water to look after your fish.

The best way to raise the pH levels in you water is to perform regular 10% – 20% water change. You should keep in mind that you do not always have to change all of your aquarium water at once. Instead, you can perform several smaller water changes. However, if you do perform smaller water changes, you should wait 24 hours in between each change, so that you do not shock the fish.

If you vacuum out all of the uneaten food in your aquarium, it will also prevent the pH levels from dropping.

There are several different things that you can add to your aquarium to raise the pH levels. For instance, crushed coral, limestone, and petrified coral will all raise the pH levels. With that being said, many people do not want to add these things to their landscaping. One way around this is by trying to hide them under some of the landscaping that you already have installed. Another method you can use is adding some crushed coral to your filter.

Baking soda will also raise the pH levels in your tank. However, with this method you will need to constantly add baking soda on a regular basis. You can’t just add it one time and be done with it. You also need to be very careful not to add too much or otherwise you will raise the pH levels too high and kill your fish. A good rule of thumb is to add 1 teaspoon per every 5 gallons.

Filtering through peat moss will be the best way to lower the pH levels in your water.

Carbon Dioxide can cause the pH levels to drop, so if you need to drop the level you can simply add Carbon Dioxide.





Don't be afraid to investigate everything having to do with maintaining your aquariums pH initially and over time and to insure that you have the proper items needed to check the pH needed for each species of fish you plan to purchase and for the tank in general. Also, if you move into salt water fish, that will require a totally different type of tank, fish and measurements.