Hi there. You should only need one pressure guage.
I think you need to re-read and absorb my instructions so you understand the best order of approach in your conditions. See below. But first, lets address a few of your additional questions.
1. Yes, you must filter 24/7 for a slam to work. Is the filter working now? To prevent clogs, only have the drain valve a little bit open. Do your best to have netted out any gunk before starting. Watch the filter pressure, and backwash any time it looks like its risen by 25%. In your case, you don't know what it runs at clean, so lets say backwash any time its at about 22.
2. I don't want you to add the cya until AFTER you've done the quick test and reported back, OR picked up an ammonia test stip from a pet store.
Here's why - this pool has putrified for 3.5 years and likely had no FC or CYA on opening. That usually means a type of bacteria has converted the cya to ammonia. If that's the case, and you add cya right now, and the bacteria is still there, it will turn the cya into ammonia and the ammonia level will keep increasing and consuming your chlorine and you won't be able to get to slam level.
So the reason I posted the "quick bleach addition" steps for before you added cya and started the slam was to prevent you from the frustration of making it harder to slam and getting stuck in swampland
If there's no ammonia and the FC holds after the quick-addition test, then you add cya, add your ch, make sure you're at 7.2 ph and start the slam. You're golden.
IF there is ammonia, there will be two ways to go, depending on how much:
1. Break it down until the FC holds, per my instructions below. Then add cya, add calcium, and follow the normal
SLAM Process
2. OR since it takes 10 times the chlorine for every ppm of ammonia, if the reading is super high, eg 10 (if you test with a strip) AND if conditions, eg water table, make a water change ok, you might be better off instead renting a trash pump to at least partly drain the pool (getting the gunk off the bottom), then adding more water, doing the now quicker breakdown of ammonia til FC holds, then adding your ch cya and slamming. Or entirely changing the water.
In some conditions, the trash-pump partial water change ends up being cheaper and easier than slamming if high volumes of ammonia are present. But they may not be.
My pool, which was way worse than yours due to 20 wheelbarrows full of leaves, took 12 bags of shock and 5 gallons of liquid 12% chlorine from th pool techs and still read 0 FC until I discovered TFP and took over
I'll post a pic to motivate you
in my case, if I'd known what I know now, though, a trash pump with a plastic tarp would ave been a bit quicker but I'm on well and in a high water able and was scared to hurt the structure.
So what you need to have on hand is:
Lots of bleach
CYA (but do the test before you add it)
Cacium to raise
Muriatic acid to lower ph
Baking Soda and Washing Soda for adjustment if needed to TA and ph
And for the first few days of slam, you're going to want to babysit that filter. You might need to turn if off now and then to clean out the pump basket.
Hope that helps. Please read over a few times. I have guests in from out of town so I won't be on the forum a lot but I'll try to take a peek in to see how you're doing.
Cheers to clear
Hi again - didnt have a chance to check back again until this a.m. Had company
With metals and a swamp, generally, you address the swamp first, metals later -- you can't treat both normally at the same time, but in this case there are other options to consider.
I have a vinyl pool so I'm actually not certain whether its best to add the calcium now or later but because there are a couple other things we should check on first that I think might help determine whether you should SLAM or consider instead a drain. So hold off on adding CH until we do a test and get the approach sorted out.
Don't put in the CYA just yet, but have it on hand. Be sure to have LOTS of bleach or chlorine (same thing) on hand.
There's a simple test I want you to do first given the number of years you've been closed AND the fact that you reported 0FC and 0 CYA. This happened to me with my swamp
The goal is to determine whether or not the pool has been subject to a phenom where a certain type of bacteria converts the cya to ammonia. Ammonia then "fights" the chlorine, making it impossible to hold at a slam level long enough to sanitize the water...until or unless you break the ammonia down. I'd originally hired pool techs to recover my swamp before finding TFP, and they never got the FC to hold But I was able to eventually. In my case, draining would have been dangerous because I have a high water table, vinyl pool, on well and the pool was built in a former catch basin. And it was spring So I didn't really have a sensible choice but to clear the water I had
With the filter running and your ph adjusted to 7.2, do this test and report back...I'll try to check in more today:
Diagnosing:
1. Test CYA level and record result (you've already done this)
2. With pump running, dose FC to Shock (SLAM) per level per Pool School - Chlorine / CYA Chart, then retest FC after 10 minutes. If FC level drops by more than 50%, then proceed with treatment for ammonia.
Treatment for Ammonia:
1. Begin a SLAM and dose FC up to SLAM level. Do not add additional CYA at this point.
2. Retest FC at 10-minute intervals.
a. If FC loss is greater than 50%, add FC to bring back up to SLAM level and continue retesting FC @ 10-minute intervals.
b. IF FC loss is 50% or less, add FC to bring back up to SLAM level. Go to Step 3.
***At any point in step A if you make several attempts, it might be worthwhile once you have an indication of possible ammonia to get a cheap aquarium ammonia test from pet store to find out just how much you have.
It takes approximately 10 ppm of chlorine to break down 1 ppm of ammonia. If you had a really high ammonia reading, I would instead consider possibly draining instead, refilling, then finishing with a slam -- this approach may also give an opportunity to reduce any metal concentration and possibly take action on the stains at the same time.
BUT, there are some moving parts here, and my expertise is not plaster pools -- For example, an acid wash will remove stains, but if the plaster is old, this may reduce its lifespan a bit. There is a no-drain acid wash for plaster stains that might be better, and there is also an Ascorbic Acid treatment that can be done. I may need to try to to reach out to a plaster person for advice if your ammonia is super high and if you decide to drain and replace water. I am thinking if you decided to drain that it might make sense to add stain remover (Ascorbic Acid) to the water, let it sit/filter a day, then drain, which should reduce stains.
SO - BACK to the slam scenario so you know what to do if youre lucky and the pool holds FC after a few quick additions. I would add the CH and CYA at that point, then start to slam...be sure to read the SLAM instructions a few times, and don't worry just yet about stains or water tint.
Step 3
3. If CYA is below 30 ppm, add enough CYA to bring level up to 30 ppm.
4. Continue SLAM as directed in the SLAM article until the SLAM Criteria of Done are met. Test as directed in the SLAM article - no longer need to test FC at 10 minute increments at this point.
When you post back, let us know if you're on well or city water, if you know the age of the pool, and if you ave any idea about the water table. If you're able to get a pic of the stain, please post it.
Cheers to clear. I know this is a lot to take in but I'm hoping to save you time and trouble on the front end here
