First year pool high stabilizer and algae

We just purchased a house in the fall with an inground pool, and finished up the season ok. This is our first summer on our own and we were doing fine until a few days ago.

We have a 25,000 gallon inground pool, vinyl liner, sand filter, automatic chlorinator, safety pool cover. We run the filter 24/7, and keep the safety cover on most of the time, but try to get the pool 6+ hrs of sunlight if we can each day that it's not raining. I currently have a Taylor Troubleshooting test kit (but have ordered the Taylor 2006 today after reading your website and several forum posts) and test daily.

Generally our ph is 7.2 and Chlorine has been running high, in the 5-10 range because once we turn the chlorinator on for 6-8 hrs, it shoots way up to the 5-10 range on my test kit, and then I shut it off and it takes a week to come back down. Alkalinity around 180. There's only 3 of us swimming it it, but we try to get in every day if we can...but we're probably averaging every other day for an hour or two.

We noticed some "gunk"/algae starting to build up around our light so I thought, Oh we probably need a dose of Algicide since we haven't put any in since we opened. That turned the water completely cloudy. So I thought, OK, well probably dead algae, we will let it filter for a day. Didn't clear up.

Took a sample in to our local Ace Hardware that does the computer water testing -- said everything was in a good range (I don't have the numbers in front of me) except the CYA (stabilizer) was 170+ WAY too high and we needed to drain 60% the pool and replace the water. Well, I know not to do that, but I am hoping that I can do some vacuuming, backwashing, and other to get us cleared up and the stabilizer will eventually go down as we lose water and top off with the hose?

I am currently using "In The Swim" chemicals, 3" Trichlor tablets, that have stabilizer in them, so I know I'm just continuing to add more cyanuric acid, but I am scared to just add bleach to my pool with a vinyl liner.

Advice to get my wonderful clear pool back?

Is it safe to swim in with cloudy water as long as the PH and Chlorine are Ok?

1. Empty the chlorinator and give away the tabs -- all forms of auto-chlorinator chlorine contain high levels of stabilizer.

2. Get K2006 -- check! on the way. Read the Best Guess page, linked in my signature.

3. Get a cheap OTO/phenol red kit (yellow/red drops) locally.

4. Order some polyquat -- about $17/qt w/ no tax or shipping @ Amazon. See www.poolsolutions.com/polyquat.html Probably want to get 4 quarts. It will keep, so save what you don't need.

5. Bleach is NOT a problem for liner pools; if it was, 10,000's of BBB method users would have gotten white liners by now. This is a pool dealer myth. But Walmart bleach -- if you get the 8% stuff, it's probably quite a bit cheaper than pool store bleach (aka "liquid chlorine")

6. Look for calcium hypochlorite locally. If you find it, make SURE it's 65% or high CHLORINE, and has calcium hypochlorite listed as the ONLY ingredient. Tell us what price you find -- $'s for pounds.

7. Use bleach to raise your chlorine levels to the OTO *orange* level (15 - 25 ppm -- you DID read the Best Guess page, right?)

8. Swimming at FC=25 ppm when CYA = 100+ ppm is FINE for people, but can be hard on swimsuits. Wear old suits, unless your pool fence is high and not see-through. (Skin is VERY chlorine resistant ;) )

9. Run your filter 24/7. Brush your pool every other day, once the FC => orange.

10. Do NOT add *any* algaecide, except polyquat. Use polyquat ONLY according to label recommendations, and ONLY until all the algae is gone.

11. PH testing will be unreliable at FC > 15 ppm, until you get the K2006. Even then, you need to read the pH within 15 seconds of adding the drops. If you wait, the result will be wrong.

12. Post K2006 results once you have them. When you test CYA, do NOT waste the test. Read, check, re-read, do it right the first time. There is only enough R0013 reagent for about 7 tests. Also, and this is IMPORTANT, for YOUR pool, do NOT test pool water for CYA. Instead, test a mixture of 1/2 pool water and 1/2 tap water. Multiple the results x2.

Since my 2006 kit is not here yet, here are the results from a HTH pool computer test that my local hardware does.
FC: 0.8ppm
TC: 0.8ppm
CC: 0
pH: 7.2
Hardness: 568ppm
Alkalinity (w/stabilizer correction): 113 ppm
Cyanuric Acid: OVR 175
Copper: 0.1ppm
Iron: 2.2ppm

I have 8% walmart brand bleach but how much do I start with? I know to dose, then let circulate, and test again before adding more or other things, but do I start with 1 gallon or 4? no idea.

I'm working on all other recommendations: kit & polyquat is on the way. Will run filter & brush once we get the FC up.

Just found the bleach calculator on another thread in this forum....recommends 8 Liters or about 2 gallons. So I will start with one gallon tonight and check tomorrow.

Update from Yesterday's posts: Pool is beginning to clear up -- clear in the shallow end & can see the white circle of the bottom drain now in the deep end. Chlorine is up to the medium/dark yellow (3-6) so we will add some more bleach tonight to get up to your recommendation.

Got my K2006 kit in the mail, here are the results:
FC: 2.8 (I just added 2 more gallons of bleach after testing this)
CC: 0.4
pH: 7.2
TA: 200
Calcium: 450
CYN: 200 (probably a bit more, it was just a little under the 100 mark)

Polyquat should be here tomorrow. Not sure how I decide if I still need it. Water is clear. We haven't backwashed since vacuuming what had settled out yesterday but pressure is fine. We plan to start brushing tomorrow.

You may not need the polyquat; if not, just save it. It will keep indefinitely, if you make sure the bottles are not exposed to sunlight. You can use it when you go on vacation or some other time.

You need to be running chlorine levels near 20 ppm, if your CYA > 100 ppm; otherwise, algae will recur. Read the Best Guess page, linked in my signature block.

With chlorine levels > 10 ppm, you'll tend to use up the chlorine test reagent quickly. Avoid this by purchasing a gallon of distilled water at Walmart, and testing a mix of 1/2 pool water and 1/2 distilled, and multiplying by 2.

Otherwise, sounds like you're on your way!

Just wanted to let you all know with your recommendations we are doing great! The pool is clear and we are feeling more confident.
Our CYN levels are on their way down, just from splashout or backwashing & refilling. 160 down from 200. So we are still keeping our chlorine higher based on the best guess chart.
We got rid of our algae with polyquat and plan to keep it that way!

Our Ph is starting to creep up to about 7.5 but it looks like that is still in your recommended range.

Is there anything I need to be concerned with on the Ph front with a vinyl liner? I didn't exactly understand your page about running high Ph is ok, sometimes, but not always. I guess I'll just keep us between 7.2-7.6 because of our vinyl liner.
Thanks again! I hope others can learn from this post & gain confidence in trying the BBB method no matter what others are telling them. So glad I found the forum & website!

As long as your pH is between 7.2 - 7.8, you are good to go! Glad things are going well. Have fun swimming!