Bought this 1985 house with IG Gunite pool in May of this year.
Initial pool inspection showed some algae and my observation confirmed that so I got busy and brought the chemistry into line. .
Shocked and kept floating chlorinator stocked with 3" tablets and had good clarity and water chemistry.
Initial water test at LPS back in late May indicated calcium a bit high and the suggestion was just to add fresh water regularly to top off the level and that nothing else seemed amiss. I do not have a copy of that original report - it was hand-written and later reports are computer-printed.
Did this (topped off water) and until a few days ago all was well.
Suddenly noticed cloudiness in the water, on 9/5/13. Had water retested (results below) and added recommended clarifier. This time calcium was noted to be way high so it was also recommended to replace some water to lower it but before I could, disaster struck.
2 days later, algae bloom in full progress. Re-shocked. No effect. Had been told on 9/5 that with calcium level high, nothing else mattered/would be ineffective until it was lowered by dilution.
Repaired stuck pump drain valve (no backflush plumbed; it's a filter cart) and set to drain. Big flood in yard. Traced other end of the PVC pipe to the front corner of the house, an open-ended PVC pipe buried into the ground going into nothing next to the front corner of the foundation, so water exchange was tedious and first time limited to about 10", but did manage to do that much and also recycle the water since it is illegal in this city (Carrollton, TX) to dump pool water in the street or storm sewer.
Had another water test and just have watched it get greener and greener.
Now on 9/9/13 the pool is completely cloudy and totally green.
Here are test results both times:
Calcium hardness, 630
Cyanuric Acid, 100+ (100 is highest they can tell)
Total Alkalinity, 120
Total Dissolved Solids, 950
By 9/8/13 the results that we re-tested, to see if the partial water exchange impacted anything, look like this:
Calcium hardness, 340 to 390 (two tests in a row from same sample).
Cyanuric Acid, 100+
Phosphates, 500 (note how much they went UP).
There's nothing like waste or fertilizer nearby - and no one has been swimming in days due to the bloom.
My plan is as follows, and I wonder if some here could comment, including any effect on a few days' delay. Scheduling all this work will consume time on days I don't have this week due to a family wedding Friday/Saturday, so I am going to have to scramble to work something out as draining and refilling and then adding proper chemicals after to keep it from coming back will take time. Sunday seems the best day to attack it...it's so far gone at this point, I'm not sure a few more days will hurt THAT much, will it? Again, comment as you see fit and tell me if that's a really bad idea to wait just a bit until the hours are actually available. Right now I would not be able to hire a pro and anyway they wouldn't solve the drain plumbing issue (see below) - I have to do that.
1. Acquire backwash hose ($20 at Home Depot, 50', 1-1/2") and hose clamp to connect in-ground drain PVC to sanitary sewer cleanout opening (about 15' away). Per the City web site, this is acceptable - even just opening the cap and sticking the hose in - to dump water though is temporary. At some point I'll dig a trench and put in the required P-Trap and plumb it permanently but right now there's no time for that.
Turns out the Jandy valve and the way the drain is plumbed, you have to unscrew the Jandy valve handle to get it to clear the stop positions, but when you do that you can then rotate it into the 4th position (180 degrees from the "both inlets open" position - two inlets joined, open at the 9 o'clock position, all inlets open at the 6 o'clock position, and the Jandy-type threaded inlet (not used except for a water feature sometimes - the Baracuda uses main suction) open at 3 o'clock. This last position, which closes both inlet positions, is at the 12 o'clock position and I only discovered this one today after looking at the valve again and realizing I could maybe unscrew the handle and get it to rotate all the way around to block all inlets - the drain valve is T'd off before the Jandy valve.
2. Dump (per LPS and others who recommend similar, but not draining the entire pool) 1/3 to 1/2 of the water and refill on my watering day (voluntary 2x per week after 6 PM restrictions at present). To do this, set the Jandy valve to 12 o'clock and also remove the filter cart (no point filtering the water being dumped) and reassemble the filter housing with it temporarily out. Opening the drain valve with the PVC connected to the sewer, this will dump through the 1-1/2" PVC/Backwash hose at pump volume and based on quick test when I turned the Jandy, seems there is plenty of pressure/volume to drain fairly quickly.
3. Refill the pool and shock it - but HOW MUCH and HOW OFTEN? I need some advice on this part, much less if draining up to 1/2 the water is enough given this is a full-fledged cloudy green mess (I do have a photo of it but can't post it right now).
What about the chlorine tabs? They have CYA and if that level went high and caused all this after only a few months, presuming that original test was checked for it but the level wasn't abnormal back in May - I have no way to know for sure - I obviously want to avoid a repeat. Had thought I might get through this season without a water exchange of this magnitude but not any more.
LPS suggests at least 1/3 of water be exchanged in this climate at the start of each season. Valid recommendation? Based on all the online material, LPS staff comments and suggestions, and the fact that the last time I had a pool was 13 years ago when we owned another house a few miles south, I am a little rusty. Plus, nobody seems to answer the same question the same way so it is hard to know what's valid and correct, versus misinformation or worse, misleading information (intentional or not).
Do plan to order a better test kit than I have (though so far I'm unimpressed with a $68 cost and $17 to ship such a small package, the TF-100 recommended here), to avoid repeated trips to the LPS but they know I have a problem and have been very helpful to run any tests I request even though they really only offer the freebie once a month per address (Leslie's).
It was a surprise, somewhat, to see the phosphate level increase after the limited water exchange, too. Not sure what to make of that and of course that is part of the algae's feeding frenzy.
I've tried to give accurate information about the pool's sizing based on info I have in the previous owner's statements and inspection report though nothing exactly specifies it. I need to do a more detailed calculation at some point, of course and will but for now I'm more interested in making wider swaths here to kill the problem completely and then start anew. Once in our other house I did a total water replacement, and this time I was hoping to avoid it but some material I read said that with CYA as high as this could be (including the 50/50 dilution of pool water with tap, to test and see about how high it really was - haven't done that yet), it might be hard to dilute the CYA enough without dumping the whole thing.
Also, and finally, it seems this whole thing went massively wrong so quickly I didn't really even have time to react over the weekend, due to the fact I had drain repairs to make and to figure out some legal way to dump water in the first place; took time researching the city web site on the weekend to find the answer but I finally did.
The initial dump took about 7 hours and only dropped it about 10", and this with constant attention and tweaking. Refilling it this time, I've essentially wasted that fresh water but there's nothing I can do about it.
Now that I have figured out the Jandy valve position which isn't "accessible" normally, I should be able to speed things up and probably can avoid a sump pump this time around, which would mean I'd have to string a longer hose from the pool to the front yard where the sewer cleanout is located anyway, than I have to with the in-ground PVC drain pipe and a clamped-on backwash hose to reach it. I had planned to buy a 50' backwash hose, trim about 15' feet for this use, and save the rest for other applications if the 15' piece were to fail later. If I don't cut it, it would work for the sump pump if I have to go that route, but the 50' length for the drain PVC to sewer isn't going to work - too much excess length to manage in that 15' distance and it would just be wrapped in circles.
In closing, I found this article online that discusses the CYA 'problem'. Anyone have any thoughts about it? It seems enough well-reasoned though it's dated 1997. The CYA level seems to have precipitated all this so I will have to watch closely...or was it first the elevated calcium followed by that? Hard to tell.
http://www.ppoa.org/pdfs/PrP_Cyanurics% ... 20Bomb.pdf
Thank you in advance.