CYA over 200

Hello I am brand new here and this is my first post! Hi all.

I have a 22,000 gal inground pool from 1972 w original plaster ...not in the greatest shape but trying to do my best. I have had this property for 13 yrs and I know how to manage pool chemistry fairly well.

With that said, I have had nothing but problems this season with green algae. I can not keep a FC reading at all. If I shock, boom few days later no FC and green starts showing up in places. I made the mistake of floating wayyy too many pucks and using powder shock so I know I caused super high CYA. I have removed the floating pucks and I'm switching to liq chlorine.

I just backwashed my green green filter and started refilling. I just tested CYA and it is over 200. Does everyone here think I should drain this pool?? If I have to I'm ready to do so but wanted to ask your honest opinion.

Do you thinking the high CYA has locked my FC..I think this might bee my problem.

Thanks All!
Dottie
 
Yes, yes and YES! You will need to drain most of the water (and refill) to get the CYA to acceptable levels.

Just depending on where you are and what type of pool you have be carefull with how low you drain the pool.
 
Welcome to the forum :wave:

How did you test the CYA at over 200? Most tests only accurately test up to about 100, tops.

If you indeed have CYA over 200, your only options are the drain/refill dance or possible RO treatment.
 
WOW ... slow on my typing this time ;)

Welcome to TFP!!!

First, how did you get your reading of 200 for CYA?
Second, if it really is that high, likely your best option is a lot of water replacement to get the CYA into a manageable range.

Care should be taken draining too much of the pool at once if you are not aware of your groundwater table.

I recommend you also start reading Pool School (button at upper right of the page). You will quickly learn the relationship of FC and CYA. For example, if your CYA is indeed 200ppm, you would have been susceptible to algae anytime your FC level was below 14ppm.
 
I am going to say you need to replace as much of that water as practical but I am going to let one of the in-ground experts recommend the safest way to to do this.

I know it involves your local water table and the method of construction used in your pool.

Can you fill in your profile and give us an idea of where you are. You might call your local county extension to see if they can tell what it is.
 
Sorry All! I will go work on my profile now.

Thanks for the all the answers. I am in So. Cal in Los Angeles...

just fyi ..I took a water sample to a local pool store and they did a CYI test by drops..I didn't really trust their reading of over 200 so I cheated and used a aquacheck strip which showed dark dark purple. After seeing that reading I knew I had a very high CYA level (I read the pool school and I know strips are a no no!) .
 
OK, then your first step should be to order one of the recommended test kits (see my signature) and start doing your own testing.

Given the 2 tests it is likely your CYA is actually high, so you could start replacing water while waiting for your test kit.

Based on your location, I am throwing this out there, the ONLY alternative to drain/refill, is Reverse Osmosis treatment on your pool. I am pretty sure this is available in your area. But, it does likely cost at least $300.
 

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The Good News-----> Drained and refilled 50% of water.
Shocked the heck out the pool

The BAD News...

I cleaned out the filter today which was a nice shady of green. I found at least 3 torn grids which need to be repaird. My backwash valve now will not go all the way down...can't get the pin under the groove. My pool light is broke off in the niche which is full of glass and water and rust. And I have black algae in more than 30 areas (I stopped counting) it comes off with my finger nail real think black and wipes green on paper. This is a big deal with it is spreading and I thought it was really dark green until I got in there with the water drained off in the shallows. Does anyone have any encouragement for me.... I can't fix all this stuff don't know how.
Almost forgot to tell you all, I have four areas with tiles popping off. I cant even count the number of tiles in the deep end. Two ares are in curves and two in straight sides of the pool. When I cleaned out the filter today there were handfuls of crumbled plaster inside on the bottom of the filter. Help..

Can someone pls give me some advice. I really feel this is the end of the this original plaster 40 yr old pool.
Sorry this is so much...I'm totally exhausted and have no idea where to start first.

Thanks and good night all.
 
Sorry to hear all that. Yikes.

Sounds like it could be time for a new tile and plaster job if the plaster is starting to fail too.

That light could be an issue of there is glass in the pool.

You know the algae solution is the shock process, but hard to say if that is the priority.

Posted with Tapatalk ... sorry if I sound short ... hate typing on phone ;)
 
To stop and kill the black algae in the larger quantity you are seeing and in very old plaster that is likely pitted to some degree, you will need to shock the pool which with 100 ppm CYA requires a rather high 40 ppm FC level of chlorine. You would also scrub the algae with a strong brush (wire is OK for plaster) to rub off the waxy surface layer to expose the roots of the algae to high chlorine levels. So you can see why high CYA levels are problematic, not only in allowing algae to grow, but in requiring a heck of a lot of chlorine for shocking.

You could do another partial drain/refill to get down to 50 ppm in which case the shock level would only be 20 ppm FC. Or you could buy an algaecide product that will work around the high CYA level, but since you eventually have to get the CYA lower anyway, I'd opt for the additional partial drain/refill and for now just get the FC level way up even though you'll be removing some if it with the partial drain/refill.

Now others may say to just give it up and have the plaster redone (whoops, jbizzle said just that while I was typing).
 
Hi All! Well truth is I was so stressed these past few days, threw in the towel, tried to give up, hired a pool man, drank some vodka and now ta da... all the hard work has paid off and I'm seeing pink FC 5ppm!

I know enough to be dangerous so the pool man I hired Saturday never did come back because he insisted on adding CYA and I told him NO way! Do you even believe this...and he wanted $$.

I went to Leslies and Secard and actually got some good help (surprised) until I got my kit and I'm happy with PINK FC!! I'm watching it closely and it has held over night and today. So darn excited (even though I know I will be draining or siphoning to lower CYA) I listened to you all.

I dumped in bleach and liq chlorine (yes measured), I think I finally hit the break point when I put in the last 2.75 lbs of hypo cal last night around 8pm. I have a feeling this will get eaten up quickly because when I brush there is some yellow. I have hit the heads off the black spots and rubbed what I can reach with a trichlor tab I had left over. I'm not sure whats next but I'm going to try my hardest to keep the FC at 5ppm like it is right now. ( i know it needs to be higher because of my high CYA for sure). There has been no change in FC and CC so fingers crossed today. I did add a few oz. of Polyquat 60 I found at K-Mart for 19.99. Am I doing all I can????
FC 5ppm
pH 7.2 (dropped from 7.7)
TA 130
CYA 110 darn
CH 500 I know source water supply is high out of the tap here too
Laughable Leslies Phosphate 500 -- you know they of course wanted me to buy No Phos or what ever that junk is called...thanks pool school.

Any advice is welcomed as I worry the FC will drop since I see yellow and black algae. I didn't consult with a professional about plaster yet, but man my 1994 ish Kreepy Krawly has a handful of plaster in the basket today. I know we are getting close and there are many pitted spots.

Need to go back to my day job now. Back lon ater.

Thanks ALL!!!!
 
FC of 5ppm is not NEARLY high enough. Your minimum according to the chart in Pool School is at least 7ppm. And if you are actively in the shock process due to the algae) then you should be maintaining a FC level of 40ppm at least.

That cal-hypo also added to your CH problems.

What test kit do you have? You keep saying pink FC, but I do not know if that is in the FAS-DPD test (which you SHOULD be using) or the little color comparison DPD test (which is only good to 5ppm I think ... which makes me fear that is what you are using).
 
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