Time to replace sand?

[Watermom]

If anyone knows of way I can do this more accurately before my Amazon shipment arrives - please let me know. What a bad time to run out of reagent!!

John

Nothing else to do. Just have to wait on that kit.

Are you testing and dosing every couple of hours today?

[jonno]

Yes. Here are today's results through of 3pm (weather here in Maryland is sunny, mid-80s, low humidity, light breeze)

8:30a FC 17.5, CC 1.5 - added .3 gal bleach (using Taylor K-2006) - increased FC by 1.5
11:30a TC between 18 and 25 - added .7 gal bleach (using old kit because I ran out of titrating reagent) - increased FC by 3.5
1:30p TC 25ish - nothing added
3:00p TC between 18 and 25 - added .7 gal bleach to be on the safe side - increased FC by 3.5

I will test TC again in an hour or so. My bleach is 12.5% so each gal should be upping the ppm by 4.8.

[Watermom]

Also, watch the filter pressure. Backwash when the pressure rises 5-10 psi over clean filter pressure. Run the pump 24/7. Looking any better yet? Keep at it.

[jonno]

I been checking the filter daily, but haven't backwashed in over a week because it was only up 3 lbs. After reading your post I decided I'd better backwash and, wow! what nasty stuff came out - green foam and very dirty water.

After backwashing and rinsing, the filter pressure settled back to 16 lbs, and I noticed the ripple on the water is a bit stronger (the return is pointed upwards for aerating). I have some Fibre Clear - should I put a few handfuls down the skimmer (until the psi increases 1 lb) to improve the filtering efficiency?

Around 5:30p the shotglass test result was between 3 and 5 (15ppm to 25ppm) so I added another .8 gal of bleach. I retested about 30 minutes after adding the bleach and it was a definate 5 (25 ppm).

I'll test again at 8pm this evening and dose as needed to bring it back up to 25ppm. Tomorrow is a work day, but I'll treat it at 8am, sneak home for lunch and again around 6p. With the filter newly backwashed, I'm hoping for improvement on water clarity.

By the way, I've seen in other posts that some pool owners have problems with their pump being too strong for the size of their sand filter. I don't think that is true for me, but here's the info. I put a new pump on in May because the old one had burned out. Same HP (3/4) and brand (Hayward) but the new pump is a Super II model. It is stronger than the old once as the psi through a freshly backwashed filter is 16 while the old pump was around 12. The connections on the pump are 2" but I have them stepped down to 1 1/2" to fit the rest of the piping. The multiport is rated 125 GPM, the filter capacity is 275 lbs of sand. The new pump is rated with a maximum output of 63 GPM at 40 ft of head (down to 31 GPM at 70 ft of head). My pump is below the level of the pool, about even with the bottom of the deep end. There's about 15 feet of pipe back to the return - so I'm guessing the pump performance output is its full capacity of 63 GPM. Do you think that the pump size is reasonable for my filter and set up?

Thanks again.

[Watermom]

Don't add the Fiber Clear. I don't know what that is and you don't anything else that might contribute to the problem. Instead, try adding some DE to your sand filter like many of us do. It may help. Read more about it at the following link. Be aware that you may not see the rise in pressure immediately. It usually takes about a half hour in my pool to see it. So, don't add too much DE. If you overshoot, backwash it out and try again.

http://www.poolforum.com/pf2/showthread.php?t=3742

The pump size sounds reasonable to me but one of the equipment gurus will hopefully chime in if they see a problem with your setup.

Keep up the frequent testing and adding bleach. I know it is a pain, but eventually your pool is going to be fun and not so much work!

Also, do me a favor. In your signature, please put that you have a Taylor K-2006. We help so many people in so many threads that it gets time consuming to have to scroll back over and over to look to see who has what. That will be a big help and a time-saver if you can do that.

[jonno]

Thanks Watermom. TC was still 25ppm at the 8pm reading so no dose of bleach at nightfall. I'll see what the TC is in the morning and report on the level, dose, and water clarity.
(Note: I'm using the shotglass method to measure TC with OT chlorine test until my R-0871 refill arrives later this week.)

Watermom wrote:

Don't add the Fiber Clear. I don't know what that is and you don't anything else that might contribute to the problem.

I found the a couple references to Fiber Clear in this forum from about 5 years ago - http://www.poolforum.com/pf2/showthr...r-sand-filters.
Oh, and here is the MSDS for Fiber Clear http://www.fiberclear.net/images/msds_091405.pdf.

Even so, I agree that I don't want to add any variables, so I'll pick up some DE tomorrow.

[jonno]

Water is much clearer this morning - I can see the pattern on the shallow end bottom and can see the dark head of the leaf scoop when it is at the bottom of the deep end.
TC was slightly lighter than the 5 level (5 OT = 25 ppm) using the OT kit and the shotglass method so I added 1 gal of 12.5% bleach. As I swept the bottom and walls, plumes of dead algae rose up ahead of the brush in most areas - but the layer was thin enough so that the "just brushed" swath was not distinguishable from the "not yet brushed" area. In days past, the sweeping would leave a obviously cleaner swath as I brushed.

I'm trickling more water into the pool so I can backwash this evening or tomorrow. Haven't been able to test pH or TA due to the high chlorine level. I'll be back at noon to test again. Sky is overcast and drizzling.

[jonno]

Yay! The titrating reagent refill was on my front porch when I came home from lunch so I was able to do a real FC test.

FC 31.5, so no bleach added.
CC 0.0

I arranged for another family member to test the FC again at 4p and I'll test once more around 6:30p when I get home.

John

[jonno]

Three titrating tests starting at noon today. Before that I had to use the shotglass method and it was a guess at best.
The water is still cloudy, but I can see the bottom.

1pm
FC 31.5
CC 0.0

4pm
FC 28.5
CC not tested

7pm
FC 27.0
CC 1.5

I'll test again tomorrow morning and see if the FC has held within 1 ppm. If it is below 25ppm, I'll add bleach. If it is 25 or higher, I think the plan is to stop adding bleach let the FC drift down to 15 (it may take a day or two), then test pH and TA. Then (dare I ask it?) will it be swim time?

[Watermom]

But...... if you still have a CC reading greater than 0.5, you still have to maintain the high cl. Sorry to have to tell you that. Since your FC didn't drop much during that time period, I'm hoping the CC reading may be is just testing error.