Problem with water being cloudy/murky.

[TheGoose]

OK, now we see that my alk and CYA are a little low, but not super low (except CYA). I will work on those two tomorrow. I don't think I have lost my sand, but I have plans to take the sand filter apart tomorrow. The dP on the sand filter rises generally over time, as you would expect. I backwash normally ever 1-2 weeks, and you can tell if the filter is getting plugged because not enough water is coming through the pool return jets.

Thanks for your advice and input.

[TheGoose]

OK, I ordered the Taylor K2006 kit. Today I'm adding baking soda and CYA to get those numbers up a little, and then I'm taking apart the sand filter.

[aylad]

Keep in mind that if you add the CYA through the skimmer, and then take the filter apart, you're going to lose your CYA...it takes several days for it to sit in the filter and dissolve. If you added it via sock, then you should be okay.

I wouldn't worry about the TA for now--get the filter working, get chlorine in the pool, and once it clears up you can tweak the rest of the numbers.

Janet

[TheGoose]

OK, added the baking soda and some CYA. Also I finally took the filter apart, everything looked pretty normal with the filter and the sand. I went ahead and changed the sand out as I was out of ideas. I noticed when putting in the new sand that the level was higher, so I definitely think that pooldoc was on to something with the fact that I've lost some sand. The pool water was immediately clearer but not totally clear. I think as the filter operates normally the water will get better every day.

What are your suggestions on the loss of the sand? I was thinking that I could add some to the skimmer (like how you add DE) every so often....or install a throttle valve when backwashing to keep the water from pushing sand out. I don't think it's just completely blowing the sand out while backwashing. I ran my hand through the waste stream while backwashing and did not notice any sand....but I know it went somewhere. With 0 pressure on the system (backwashing) I'm getting 50-60 gpm through the waste line (bucket calculated) but the filter is designed for 60 gpm.

[TheGoose]

OK, here is a slight update to this thread. I received the taylor test kit and I'm impressed. I wish I had bought this thing years ago. I had used several different kits in the past but this one is definitely top notch and accurate. It even comes with a little book that is full of useful information about not only the test kit but why the colors sometimes are flaky.

Here's my #s for today.
FC = 3.0 (as measured with the .2 ppm method)
CC= 1.0
Alkalinity = 200 ppm (may be slightly less, I elected to use the 25 ppm multiplier to save on reagents).
Hardness = 300
pH =7.4
CYA = 30

Pool water is much better after changing the sand. I'm still curious as to why I have lost sand. When I bought the pump/tank I sized the tank for the pump. The tank is good for 60 GPM, but I did measure the open ended output and it is in the 60 GPM range. I'm curious if any of you had run into this problem and if I need to simply add a bag or two of sand per year to prevent this from happening.

Even though my water has gotten much better it still is not that "crystal clear" I was looking for. I'm seriously considering switching back to a DE filter and I noticed that most of the mods etc. use sand filters. Is the hassle of adding the DE really not worth the better efficiency?

Thanks for your replies.

[Watermom]

Although many people swear by their DE filters, ALL the mods use sand filters -- although Janet switched to Zeo a year or two ago. It is so much less hassle and honestly, I'm not sure my water could get any clearer with something else. Have you tried added a little DE to your sand filter?

Since you have CC of 1.0, you need to shock the pool again. For a CYA of 30, that would mean shocking it up to 15ppm. I would just use bleach if I were you since you are battling cloudiness. In an 18K pool, each gallon (4 quarts) of 6% bleach will add about 3.3 ppm of cl. Keep your chlorine at shock level as consistently as you can until your water clears, you have no higher than 0.5 CC and you can go from sundown one evening until no longer than 2 hours after sunup without losing more than 1ppm of cl. It may take a couple of days, but with a working filter and consistent shock level, it should clear up. Also run the pump 24/7 while you are trying to clear it.

[TheGoose]

Thanks so much for your info.

I tested the water again this morning. I really love this Taylor test kit, thanks for the tip.

OK, yesterday evening when I tested it was getting a little dark, so I wanted to double check all my tests in good sunlight. Everything matches up except the CYA. I messed that one up, the CYA is most likely around 10 or so. When I get the tube to the 30 ppm mark, the dot fades significantly, but not completely. I can fill the tube all the way to the top before it disappears. Pool store tested it at 10 ppm, which is what I think is true. I know that I only have a few more tests left with this kit but I think I can get the CYA test solution at Wal Mart.

Here are this mornings #'s.
FC = .8 ppm
CC = .6 ppm (both using the .2 ppm method)
pH = 7.4
TA = 200-225 (using the 25 ppm method)
CH =300-325 (using the 25 ppm method)
CYA <30 (less than 30). Most likely around 10 ppm.

Water is looking much better, starting to get that "blue" tint to it again. Even lately when the water has been improved it has still had a green tint. Yesterday I scrubbed the walls and trouble places like corners and jets where the algae tends to cling. I also set my filter to run 2 hours during the night so that it doesn't sit so long without being turned over. I had it set to run from 9 am to 9 pm.

What I'm really interested in is has anybody ever come up with a solution to keep the sand level in the filter at the right level? Add some to the skimmer? Pop the top? I think if I marked the level in the filter using a really bright light I could keep tabs on it. When I had the filter apart I noticed that it allowed some light to pass through, so I was thinking that I could hold a Qbeam next to it at night to see if I could see the level. Kind of like when you stick a flashlight next to your hand at night and can see the red glow etc. I'll make sure not to melt the filter though, so don't worry about that, LOL.