Time to replace sand?

[jonno]

Thanks Watermom. This mornings FC was 23.5 so I added 0.3 gal of 12.5% bleach, at 6.8 ppm per gal, this should raise the FC by 1.5 to hit the 25 mark. I'll do this every hour or so throughout the day and see if I can get someone to do it more frequently tomorrow (a work day for me).

I'm off to the pool store now. I never thought I'd darken their threshold, but I'm almost out of R-0871 and my re-order from Amazon is not due until the end of the week.

If in any of the FC tests today is 15 ppm or below, I'll test pH - otherwise I'll check it in the morning and add muriatic acid if it is above 7.0. The water is definately blue again. It's still cloudy but less so than yesterday.

[Watermom]

I'm keeping my fingers crossed that two consecutive days of non-stop babysitting this pool will make a difference. Keep us posted!

[jonno]

Just returned from a 2 hour quest for R0871 FAS-DPD Titrating Reagent. Leslie's told me over the phone that they had it in stock, but they had only the DPD Reagent #2 (item # 81345). The item I need is in their online catalog, #81348, but not on the shelves. Tried 3 other pool stores - no luck.

I ordered 2oz of R-0871 from Amazon last Wed, but it won't arrive until Thursday. I had to resort to Carl's shot glass method and mixed 1 part pool water to 4 parts distilled water then used my pre-Taylor K2006 test kit to test for total chlorine and multiply the results by 5. Since the highest readings I can get with my old kit maxes out at 5 ppm, the best I can do is get a vague sense of whether I'm dipping below 25 ppm (since 5 x 5 = 25).

When I did the test it appeared to match the color for 3. Multiplying by 5 gives a result of 18ppm - but it is a guess at best. Based on that I was conservative and added 1/2 a gallon of 12.5% bleach - waited 30 minutes then retested - it seems to have pushed it up from the 3-ish level to the 5-ish level (x 5 = 25ppm).

I'll try it again in a few hours and adjust accordingly. Every pool store I visited said the max chlorine level they can test is 5 ppm. 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

[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.