1st test with the TF-100; could use some advice

[edavis6678]

I bought my house with the pool about 3 years ago and have been doing the pool myself or the past year or so. (fired the pool guy that came with the house, since he didn't seem to do much than add chlorine in large doses).

For the past year I've been using the basic Taylor kit that I got from Leslie's and was getting pretty good about keeping my CL, PH, and Alk in balance, but i am still using up the last of my Trichor Tabs and Powder (once done, I'll be looking toward using liquid). I began educating myself on pool chemistry, i stepped up to the TF-100 kit to get a bit more information about where the pool was (just arrived today). I never seem to have algae, and the water has generally been clear, swim-able and never irritating to the skin or eyes. I scrub and clean the pool on a weekly basis; check the levels almost every day, or at least 4-5 times a week (more as it's getting warmer). The pool doesn't have a heater, so it's typically doesn't get too warm, although it is in full sun most of the day and last summer got up to nearly 85 degrees or more. I was using some really expensive phosphate stuff I got suckered into buying from Leslie's, and occasionally I've put in the pool clarifying gel from time to time to make the pool super clear. (although it makes me change the filter more often) I use fiber paper material for the filter, rather than DE (wife doesn't like DE), and change it on a regular schedule. (i don't back-wash, but just fully clean it each time). I run the filter in the morning hours for about 3 hours, I've been told I should run it longer, or switch it to a 220v variable speed pump to save on power, but honestly I've run it for longer and don't seem to see a difference with water quality, although my power bill does show it. I don't have much mess in the pool unless it's windy; I don't any leaves at all so cleaning is pretty easy.

I do know the pool was built around 1963. I have some plaster stains on the bottom of the pool in a quite a few places, but other than it not looking "perfect" it doesn't seem to bother me too much, (although when I've had some guest come over they look at the pool a little weary) . I have a few spots where the plaster has chipped off (at the drain and at the steps in the shallow end). I think the pool was re-done in the mid 80's with some new coping and pipes, probably new plaster as well, (all of the pipes are PVC). I'd like to at some point get the pool re-plastered but I just don't have the resources to do that just yet. The pool is between 25-30K gallons. (it's 15-16ft wide, 28-30ft long, with about 8.5ft depth -- almost rectangle with a nook for the steps in the shallow end. So, here are my results -- (most were tested twice to be sure; especially the CYA and Calcium since I've never done those before.)

CYA: 120
ALK: 100
Calcium: 1275 (I did this test 3 times) - it took 51 drops to make it blue
FC=5.5
CC=0
TC=5.5
PH=7.4

With my CYA so high, does that mean I have to keep the Total Chlorine higher in order to avoid getting Algae? I usually try to keep my TC at about 2-3ppm and never seem to have algae problems; the water is clear too. (it measured high today cause I added some Chlorine yesterday - and by the look of it, added a bit too much).

I guess, the question here -- The CYA levels are too high. (along with the Calcium). I ran the PoolMath and it said that I basically had to drain 60-70 percent of the pool's water to bring the levels down to the 30-40 range. That's a very expensive endeavor and really having some issues with that since CA is in a drought. By my calculations, draining the pool will cost me roughly $250. (but this is based on my regular water usage; i'll have to call to confirm since i know the water usage goes up the more water you use) -- perhaps it may be worth doing since i may end up using more chlorine in the long run to keep the levels upl.

Anyways, If i have the concept correct, when I have the CYA that high, does the Chlorine not work as well, and to keep algae at bay I need to use more and more Chlorine? And if that's correct, why am i not seeing the algae when I regularly keep my TC at 2-3ppm? when i look at this chart: http://www.troublefreepool.com/threads/2177-Chlorine-CYA-Chart it says I need to keep my FC @ 8.7? that seems insanely high.

so in conclusion, i seem to be a bit confused at what I should do....is the pool safe to swim in? Maybe there's not algae, but does it have tons of bacteria...I have some friends coming over for the 4th of July...what can I do before then? Is draining the pool the best route to go? Any advice about the draining the pool?

Thanks for reading - I appreciate any feedback

 

[Patrick_B]

Welcome to TFP!

I hate wasting water or money, but the Cya being high will cost you much more in Chlorine. You need to do a major drain and refill.

Technically, its not that it doesn't work as well, it just takes a lot more to do the same job.

If your calcium number is correct, you need to drain/refill based on that alone. North of 1000 will be a problem by causing calcium scaling in your pool.

Drain and re-fill as soon as you can to be ready for the party is my advice.

 

[Kiss4aFrog]

You have "clear" water at this point and a few questions. You said "it measured high today cause I added some Chlorine yesterday - and by the look of it, added a bit too much". From your numbers you are still low for that much CYA.

Your CYA is very high but the CYA / chlorine chart is correct. Yes with the CYA level that high the chlorine doesn't work as effectively so you need to keep more FC in the pool to do the same amount of cleaning of the water. You need to replace water to lower your CYA to lower your needed FC level to a more appropriate 2-3 ppm level. Right now you should maintain 8-9 ppm to properly maintain the sanitation of the water. Not seeing algae isn't an indication of correct FC levels only that there is enough to keep the algae at bay. It doesn't indicate that there is enough chlorine to properly oxidize the bad "stuff" in the pool.
Is the pool safe to swim in . . . yes. Even when at a SLAM rate of say 20-25 ppm it's usually considered safe.

The CH is way high. Your number is four times what it should be. I'd try that test one more time with a new sample from today. If it's still that high it's just one more reason why you need to drain the pool and replace some water. You want to make that choice to drain before you waste the time and $$ in chemicals treating water you know you need to get rid of.
From Pool School: A plaster pool should have CH levels between 250 and 350 if possible. And: You lower calcium by replacing water or using a reverse osmosis water treatment.

Is there any reason to believe that the water you'd use to refill has that high a calcium level ??

IMHO I think you need to drain but I'd wait to see some other replies before pulling the (drain) plug.
If you have people over to swim before you drain the pool I would make sure you bring the pool up to the proper FC level for your CYA at that time as recommended in the chart or a bit more as you know from a heavy load of friends you'll use it up a bit quicker.

To make it easier on all of us it is helpful if you add some info to your "signature". Saves you time in posting and saves someone from having to ask.
Signature
Please put the following information in your signature.
1. The size of your pool in gallons
2. If your pool is an AG (above ground) or IG (in ground)
3. If it's IG, tell us if it's vinyl, plaster/pebble, or fiberglass
4. The type of filter you have (sand, DE, cartridge) and, if you know, the size, model number or flow rate of the filter.
5. If you know, please tell us the size pump in HP. Also mention if is it a two speed or variable speed pump.
6. Date of pool build/install, particularly important if less then a year old.
7. Other significant accessories or options, such as a spa , SWG, or cleaner

 

[Casey]

You really need to get that CYA and Calcium down. There are no ways around it. I would suggest looking at this chart :lookhere: Chlorine CYA Chart. With your CYA being so high, your chlorine level is *insanely low*. Also, read :lookhere: ABC's of Pool Water Chemistry.

Let me ask you, does your water look like this?



Because it can if you follow the TFPC way. It's really up to you to want to learn and understand the articles in Pool School.

Welcome to TFP. Congrats on the test kit. You're on your way to owning your pool.

 

[edavis6678]

I'm more convinced now that I need to drain, (Spoke with co-worker with pool and he concurs too). I guess now i need to look into the equipment needed and where I can dump the water and the basics and process of draining. (I'll search for some posts here). I was told i can rent a pump from Home Depot, but I'm more worried about how long it will take to re-fill and other special things that I could do when it has no water. (any treatment of the plaster or additional cleaning i can do, etc..) and any start-up chemicals I may need once it's refilled and how long it takes to stabilize the new water....

 

[Kiss4aFrog]

To dump water can't you just turn the skimmers off and pull water from the bottom and use the pools pump to pump to waste or is it that the water has no place to go in your yard ??

 

[edavis6678]

I have no skimmers and I don't have a place to dump the water in the yard (at least not 30K gallons) -- I have a clean-out near the back of the house, may try to tap into that to have it go through the drainage pipe through the house, that goes to the sewer...