drain pool?

[irvinenewbie]

numbers:
FC goal 4-8
CC 0-0.5
pH 7.8-7.9
CH 680*
TA 80
CYA 50

I noticed more MA requirement and more frequent algae breaks. Pool has natural aerator that increases pH. Is higher MA demand due to high CH? Does this pool need to be drained? Any specific instructions as to how much to drain? Thank you.

 

[JasonLion]

The correct next step depends on what your fill water CH level is. For relatively low fill water CH levels, replacing a lot of water is a good next step. But for rather high fill water CH level the best plan would be to see if you can get through the season with CH still below 1,000.

PH increases are not related to CH levels. PH increases usually have to do with how high TA is, higher TA means more PH drift. I suggest allowing TA to go down to 60 and see if that improves things.

 

[irvinenewbie]

tap water CH approx 125. How do you interpret that number? pool was partially drained 2.5 years ago. CH went from 600 to 350. Now it has climbed back up. just FYI.

discovered 1 of the 3 returns pointed downward. repointed up to aerate and bring down TA. It usually hangs around 70.

Thanks.

 

[duraleigh]

For relatively low fill water CH levels, replacing a lot of water is a good next step.

Your fill water is pretty low. Like Jason suggests, I would replace enough to get your total CH down around 300-350.

 

[Isaac-1]

Are you adding anything that will raise your CH level? this includes Cal-Hypo based dry chlorine products (cal-hypo shock), hardness increaser, basically anything with Calcium in its name?

 

[irvinenewbie]

Are you adding anything that will raise your CH level? this includes Cal-Hypo based dry chlorine products (cal-hypo shock), hardness increaser, basically anything with Calcium in its name?

Good question. No, just bleach and MA. Water source differs (river vs. well) during various seasons. This area is notorious for having hard water. I was surprised to see the CH number for tap. perhaps now water supply is well.

Thank you!

 

[irvinenewbie]

I have not had chance to drain pool yet. Had water tested at pool store, was told salt level is >3000, TDS >5000, and that pool definitely needs to be drained.

2.5 years ago, salt was 2500 before it was drained by half and refilled. I did not have salt retested after the refill. I don't know the source of salt when I inherited the pool. I have not added any salt since I took over the maintenance. Where did salt come from since the refill?

another unrelated question. this is a very trustworthy pool guy with over 40 yrs of experience. he keeps CYA at 80 in the summer, but chlorine at 2-3 and no algae. this is contrary to the CYA/FC correlation chart. How do you explain this?

Thank you.

 

[duraleigh]

this is a very trustworthy pool guy with over 40 yrs of experience. he keeps CYA at 80 in the summer, but chlorine at 2-3 and no algae. this is contrary to the CYA/FC correlation chart. How do you explain this?

Blending the advice from this forum with another source almost never agrees and you end up in the middle. If his advice makes sense to you, you should stick with it.

 

[irvinenewbie]

I have not taken the pool guy's advice, have always followed the pool calculator. Had to go there to get equipment fixed. Just wanted to understand why he can get away with doing something "wrong" for 40 years.

 

[ROB N]

If he has a SWCG those would be viable numbers... Did you ask him how often he has to drain his pool??? There are many variables... BTW Your salt came from the byproduct of the chlorine you added. It builds over time.

 

[aa62579]

Bleach adds salt. Slowly, but an increase of 100ppm of salt each month could be common.

 

[Richard320]

pH needs to go down, for sure.

Your CH number closely parallels mine. I'll tell you from experience, it will only get worse as the Summer progresses. The way to stay on top of it is to drain off a few inches at a time and use it to water the lawn. Forget about the target numbers - you'll never be able to keep CH below 400 without wasting a whole lot of water.

As for the pH rise, it's the spa. I adjusted my valves to return maybe 20% to the spa. I also stuck a spray can cap over the air intake for the spa returns to minimize aeration. With TA down at 40-50, my CSI stays low and the pH stays in the safe range for about a week at a time.

 

[duraleigh]

Just wanted to understand why he can get away with doing something "wrong" for 40 years.

There is no black and white right or wrong. BBB is about understanding the effects adding chemistry will have on your pool and then knowing how to test and dose accurately so the results are predictable.

The Pool store guy's numbers are really not too far away from the guidelines we suggest. He apparently has a set of conditions that allows him to operate successfully just outside of our guidelines which are intended for a broad audience with a wide range of conditions.

You might try those same guidelines and fail miserably because your pool is different.....or, it might work for you.

What we suggest is applicable over a broad spectrum of situations and will keep anyone's pool sparkling all summer.