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Kitty Litter in Los Angeles: Properties of different brands

This page documents my experiments with various kitty litter brands in June 1997, when I was setting up a freshwater planted tank using a substrate of kitty litter with sand on top, a la Dan Quackenbush. It took me a while to find a couple of brands which worked for me without raising the tank's pH - Hopefully this info will save some work for other folks trying to do the same thing!

For pictures and descriptions of my two freshwater tanks, you can look at my aquaria page.

Read on for a description of how the results were obtained, or skip straight to the summary at the bottom of the page.

Experimental method:

(Very unscientific. <grin>)

  1. Obtained reverse-osmosis water from the Glacier vending machines outside of Vons supermarket. Using the Aquarium Pharmaceuticals pH and hardness tests, the water is at pH 6.8, hardness 30ppm.
  2. Poured RO water into small kitchen bowls which hold about 1.2 cups (~300mL) each. To make sure the bowls would not affect pH, I let one bowl with RO water sit overnight - pH did not change.
  3. Poured a handful of each brand of kitty litter into the bowls. I stirred up the kitty litter a little after it was in the bowl - some brands clouded the water a lot, others only a little. I waited until most of the cloudiness settled (less than 1 hour) before testing the pH of the water in each bowl.
  4. If the pH in the bowl hadn't changed very much at the time of this first measurement, I let the bowl sit overnight and measured again the next day.

Note: pH tests were made with Aquarium Pharmaceuticals pH test (range 6.0-7.6), and Wardley's High Range pH test (range 7.6-8.4).


Brand Name pH
1st time
2nd time
Ingredients as listed on package Water cloudiness
Hartz pH5 Scooping Cat Litter 6.6 6.0- "a special clay mined in Georgia" Clouds slightly when stirred; settles out in a few seconds Made of fine chips (~1mm diam) which soften but stay separate in water.
Lasting Pride Scoopable Cat Litter 6.8 6.0- Ground Clay Clouds slightly when stirred; settles out in a few seconds Made of fine chips (~1mm diam) which soften but stay separate in water.
Dr. Elsey's Precious Cat Premium Cat Litter 7.0 8.4+ Natural Clay Clouds a lot; turns into a mushy clay mass.
Care Free Kitty Scoopable Cat Litter 6.8 8.4+ Ground Clay Clouds a lot; turns into a mushy clay mass.
Scoop Away Free 7.8 - Natural minerals and clays Clouds a lot; turns into a mushy clay mass.
Natural Select Scoopable Cat Litter 7.8 - bentonite clay; sodium bentonite Clouds a lot; turns into a mushy clay mass; also swells up a lot more than the other brands.
Pet Gold Plus, Scoopable Cat Litter 7.2 - Ground clay Clouds a lot; turns into a mushy clay mass.
EverFresh, Premium Clay Litter 6.8 7.4 Clay Clouds slightly when stirred; settles in a few seconds. Made of coarse chips (1-4mm diam) that remain separate and hard in water.


Only two brands are acidic instead of basic: Hartz pH5, and Lasting Pride. I used Hartz pH5 in my 29-gallon planted tank, and the results have been great. The plants don't seem to mind the acidity of the substrate.

One interesting detail was the "mushiness," or tendency to cloud the water, of many of the kitty litter samples. Both Hartz and Lasting Pride consist of small grains about 1mm in diameter. They feel slightly mushy (i.e. not hard as rock) under water, but still remain separate grains, and don't cloud the water very much when disturbed. This is a great advantage when uprooting your plants! Most other brands immediately released clouds of very fine particles into the water which could take hours to settle. (After being in my tank for a while, the Hartz pH5 does cloud my water somewhat with fine particles, when I uproot plants. It's still nowhere near the cloudiness that the other brands caused.)

The pH5 doesn't actually affect the pH of my tank water very much. It's sealed off from the water column pretty well by a 1 inch layer of #16 silica sand.

Where to get it

I got Hartz pH5 at the Sav-on market on N. Lake Ave in Pasadena (or maybe Altadena - I'm not sure just where the boundary is). Lasting Pride can be found at Wal-Mart.

Distributor of Hartz pH5:
The Hartz Mountain Corporation
Harrison, NJ 07029
St. Thomas, Ontario N5P3W7, Canada

Distributor of Lasting Pride:
Oil-Dri Corporation of America
Chicago, IL 60611

Feel free to email me with any comments or questions about this page. I'd be interested in knowing other folks' results with different brands of kitty litter, or the same brands in different parts of the world. / 13 Dec 1997

Up to Fertilizer <- Plants <- The Krib This page was last updated 23 June 1999