See
this old post that describes the structure of the pool/spa chemical industry. Clorox has always made bleach but entered into the swimming pool and spa market by sharing its brand with KIK Custom Products in 2014 as described in
this article and
this press release. KIK Custom Products bought the BioLab pool/spa chemicals business from Chemtura in 2014 and Clorox partnered with them to get their brand to be used for other chlorine products including Trichlor tablets as Clorox seeks to broaden their chlorine products and brand more into the pool and spa market explicitly while KIK leverages the chlorine brand name to other pool and spa products (e.g. DE filter media, clarifiers, etc.).
KIK has many chlorine product brands, but it is not the only player in the market. The other large player is Lonza Group via their Arch Chemicals acquisition in 2011. Secondary players include Chem Lab Products with their Kem-Tek brand while Alden Leeds and N Jonas private label products.
So the bottom line is that there is enough competition especially between KIK/Biolab and Lonza/Arch that the Clorox branding is not any sort of takeover and such branding was launched in 2014 anyway.
In my 2007 thread on the
Cost Comparison of Chlorine Sources I used Leslie's website for much of the pricing and for Trichlor I found $77 for 35 pounds while
this link shows today's price as $100. That's a 30% price increase over 8 years. However, you can see in
this archived Leslie's page from 2014 that their price in January was $100 but discounted down to $80 and in
August, 2014 it was discounted to $85. If you look at
this Leslie's page from August 2013 you will see the same kind of discounting. So mostly Leslie's is not currently offering their 20% discount right now.
intheswim.com in 2014 had chlorine tabs at the same price as
today.
So I don't see an across the board price jump from last year to this year from everyone. It seems selective, mostly Leslie's not offering their normal discount. Keep in mind that some of these very inexpensive Trichlor tabs are of lower quality and are not compressed as well so can crack more easily or dissolve at different rates.