I bought the 4 step "Members Mark" system, absolutely could not get chemical levels right, contacted Sams, found out the 4 step process is produced for them by a company called ClearOn. I called ClearOn and was astonished that they don't even understand these chemicals they make and sell much. Bottom line, they recommended I go to a pool company and buy components their products don't offer, which are needed to balance my pool. So, this 4 step process they sell will not even take care of all things needed to maintain a proper pool.....but by the way it's labeled, it appears as though that's the way it works. NO WONDER my pool, full of brand new water, has yet to test ideal on anything other than chlorine and free chlorine. ...its not going to using this 4 step system sold at Sams. I am so over it with this stuff. I will be returning these 4 containers and moving on to a new pool maintenance system. This is so aggravating, and I feel misleading.

Read the description. Dont know why but this is stabilized shock which makes no sense to me. Stabilizer in this shock concentration jacks up your cyanuric acid (CYA) readings and the ONLY way to reduce it back is by draining and refilling water in proportion to amount you need to reduce CYA by. You want non-stabilized shock, so it does its thing and goes away letting your regular chlorinator (with stabilizer) do its thing. CYA does not evaporate. My CYA shot up to 160 before I realized the shock was stabilized. 30-50 is normal. Higher than 50 actually inhibits the chlorine from doing it's sanitizing work. I had just converted to salt a week ago, and now I need to drain 75% of my water out to get CYA levels down, and reset all my other chemicals. Not happy.

I had renters move out of a house with a pool early in the summer and am making repairs in order to sell in. They left the pool in bad condition. In the past, I have purchased dry shock from Sam's Club and was very happy with it. My pool has only 8,500 gallons, so after getting it clear again, one pack is more than enough each week for maintenance. When I saw that Sam's Club had changed vendors, I read the reviews online while standing in front of it at the club. Some were good, some not so good. One reviewer in particular, said that he used the previous brand with no complaints, but with the new shock, it took twice the amount he normally used to keep the algae at bay. I figured the negative reviewer had just gotten a bad batch and proceeded to buy it. I had the same experience. After getting the pool clear using several packets, using only one pack weekly wasn't enough and my pool kept turning green. After trying it several times, I finally brought what was left in the box back to Sam's and let them know I was very unsatisfied....something I have only done once or twice in my life. My money was refunded promptly, but I would rather have their old shock back as it was reasonably priced and much easier to use than constantly buying and transporting liquid chlorine. Hopefully, my comments to customer service and this review will help in getting a better dry shock back in stock at Sam's Club.

Never had problems with our pool until now. Using this allowed mustard algae to grow with reckless abandon in our pool even with triple shocking it. Didn't realize how counterproductive it was to continue dumping copious amounts of this garbage into the water in our attempts to rid the algae. We've barely been able to use our pool this summer because our weekends are spent scrubbing the walls and scratching our head about what has happened to our beautiful crystal clear water. Wish I would've researched this stuff before wasting any time and money. JUNK! DON'T POLLUTE YOUR WATER WITH THIS JUNK!!

Something changed with this years formula....i have gone through a full box in two and a half weeks it will not bring up my chlorine levels even when combined with the chlorinator using members mark tabs. Ive been maintaining my pool the same way for years and have had 4tests from leslies in the last two weeks. This last test even with putting 3 bags of shock in is showing very low chlorine and they recommend another 3 bags.... The big issue i think is the 55% available chlorine in this versus leslies brand or other top tier brands. Two cousins having same issue....one put one bag of the Leslie's shock in and raised chlorine levels by next day. Prior to that like me he went through about 6 bags of this garbage in a week. Im going back for a refund

I've been buying pool shock from Sam's Club for the past 4 years then noticed they only carried the Member's Mark brand. Big difference, as in, it does not last as long, takes about twice as much to achieve the same desired level of chlorination. Granted, the hotter weather and more swimmers will eat chlorine but having kept a log since early 2000's I've found we're adding this product nearly twice as often as before. The only pro is it's quick dissolving... Cons? We're using about twice as much to achieve the same PPM levels.

I have bought shock from Sam's for years and never had an issue. This year I used two bags one day, and two bags the next day. My Cyanuric acid level went to 290. I was reopening my pool so the shock was the only chemical in the pool. I have a large pool and I had to drain about 6000 gallons and refill with fresh water to get the level back down to 78. I will be going to Sam's club today to ask If I can return the unused portion of the box. This is the first time I have had problems with shock bought from Sam's. I will not be using this product in the future.

Not sure why all the bad reviews on this. It is for chlorine levels, not ph or alkalinity. Different products do different things obviously. Do some research on how to get other your other readings up to standard. This works great for shocking your pool

Have owned pool for 13 years and never had the issues like we have had using this product. Takes way to much product to raise chlorine level ( I can usually use one or two bags of another brand) and then your Cyanuric acid levels will be way to high making chlorine almost ineffective resulting in having to drain pool and refill.

I started using the Sam's Club tablets and shock for the past two years. My pool chemistry was always fluctuating and this summer it got crazy. Appears that in Florida, where I am, you do not want to use this type of chlorine. It brings your cyanuric acid (chlorine stabilizer) up to the point where no matter how high your chlorine level that you test in your pool algae will still grow. The stabilizer will not let the chlorine do its job. After a lot of hassling and research the only way I was able to break the cycle was to put about 8 lbs of calcium hypochlorite pool shock into an 18,000 gallon pool. I did contribute to my own problem because each time I saw algae growing I would use the Sam's Club shock which just exacerbated the problem.