Will Draining Water Help With Algae?

[HermanTX]

Ok thanks. Does that mean I can ignore the FC, CC, & CYA tests? (I don’t mind saving some of the reagent ha.)

Fill water will not have any CYA and very little FC - no reason to test for these and CC.

From Post #87
test your tap water or whatever you will use to fill the pool after draining. Only test pH, TA and CH of that as there will be minimal if any FC and zero CYA. Keep these separate from your pool test. On the app I created a second pool called Home Tap Water - I then put the test results there. These tests will provide an indication of what your pool water may be when you fill it. It won’t be precise because you are mixing it with some existing pool water but it is good info to know for future.

 

[ugadawgs311]

Fill water will not have any CYA and very little FC - no reason to test for these and CC.

From Post #87
test your tap water or whatever you will use to fill the pool after draining. Only test pH, TA and CH of that as there will be minimal if any FC and zero CYA. Keep these separate from your pool test. On the app I created a second pool called Home Tap Water - I then put the test results there. These tests will provide an indication of what your pool water may be when you fill it. It won’t be precise because you are mixing it with some existing pool water but it is good info to know for future.

Ok, I finished testing my hose fill water. The results are:

• PH - at least 8.0 if not higher
• Total Alkalinity - 40
• Calcium Hardness - 30

All the numbers seem to be "normal" for regular tap water. Fortunately, I think this gives me a lot of wiggle room with the CH, should any more get added in the future. Also, I believe that once I add chlorine, the PH will start to decrease - is that correct?

 

[HermanTX]

Ok, I finished testing my hose fill water. The results are:

• PH - at least 8.0 if not higher
• Total Alkalinity - 40
• Calcium Hardness - 30

All the numbers seem to be "normal" for regular tap water. Fortunately, I think this gives me a lot of wiggle room with the CH, should any more get added in the future. Also, I believe that once I add chlorine, the PH will start to decrease - is that correct?

You have vinyl pool so CH not as critical. My home tap water is 130 ppm CH and some other areas are much higher so feel fortunate that you are at 30. Do you have a water softner system? Just want to verify as that takes calcium out of the water.

TA controls the rise of pH. You reduce pH with MA. So have a gallon of that on hand to lower to 7.2 before you start the SLAM.
Thanks for the results.

 

[ugadawgs311]

You have vinyl pool so CH not as critical. My home tap water is 130 ppm CH and some other areas are much higher so feel fortunate that you are at 30. Do you have a water softner system? Just want to verify as that takes calcium out of the water.

TA controls the rise of pH. You reduce pH with MA. So have a gallon of that on hand to lower to 7.2 before you start the SLAM.
Thanks for the results.

Nope, no water softener system. At least not that I’m aware of.

Ok, so first I need to lower PH to 7.2 prior to any chlorine or SLAMing? I think I have some MA. Of course I’m stocked up on CYA, Chlorine, calcium increaser, and sodium bicarbonate, but maybe not the first thing I need ha.

 

[mknauss]

calcium increaser, and sodium bicarbonate,

You will not need the calcium at all - see if you can return it. You very likely will not need the baking soda.

 

[ugadawgs311]

You will not need the calcium at all - see if you can return it. You very likely will not need the baking soda.

If I won’t need any calcium, does that mean it’d be ok to use a cal-hypo shock when needed? I ask because I already have around 30-40 one-pound bags that I’ve purchased over the off season while on sale. I’d hate to let them all go to waste. Based on some research, I don’t think they have any CYA, so that shouldn’t be an issue. And since I have such low calcium in my water to begin with, adding the calcium that’s included with the shock shouldn’t hurt, right?

 

[PoolStored]

If I won’t need any calcium, does that mean it’d be ok to use a cal-hypo shock when needed? I ask because I already have around 30-40 one-pound bags that I’ve purchased over the off season while on sale. I’d hate to let them all go to waste. Based on some research, I don’t think they have any CYA, so that shouldn’t be an issue. And since I have such low calcium in my water to begin with, adding the calcium that’s included with the shock shouldn’t hurt, right?

To a point. You can still have calcium scale in a vinyl liner pools. You need to watch your CSI with pool math.

Calcium Scaling

Calcium scale on your pool is something we all want to avoid. With some elbow grease and a pumice stone for pools we can help you remove this eyesore.

www.troublefreepool.com

 

[mknauss]

As PS states, monitor your CH level. I would not go above 200 ppm.

Also, be very careful adding CalHypo to the pool. If any granules sit on your liner, they will bleach them.

Do be ware that Cal Hypo is one of the most dangerous chemical we use for pool care. It can become unstable pretty rapidly.
Read Chemical Storage and Safety - Further Reading

 

[ugadawgs311]

To a point. You can still have calcium scale in a vinyl liner pools. You need to watch your CSI with pool math.

Calcium Scaling

Calcium scale on your pool is something we all want to avoid. With some elbow grease and a pumice stone for pools we can help you remove this eyesore.

www.troublefreepool.com

As PS states, monitor your CH level. I would not go above 200 ppm.

Also, be very careful adding CalHypo to the pool. If any granules sit on your liner, they will bleach them.

Do be ware that Cal Hypo is one of the most dangerous chemical we use for pool care. It can become unstable pretty rapidly.
Read Chemical Storage and Safety - Further Reading

Ok, thanks. I'll be sure to keep an eye on the CH level and not go above 200 ppm.

 

[ugadawgs311]

Update: pool is now drained, and steps are being repaired, however I just learned that I'll need to keep the steps mostly dry for 8 days, which means I can't refill the pool until then. Will it be ok to leave the filter off for that long? I guess I could turn the filter on since the deep end still has water. The skimmer is already closed off, and I can just have water return through one set of returns while the water is below the skimmer and return jets.

I bet the water will be a nasty green/brown color by the end of 8 days, but I guess that's what all the LC is for!

 

[mknauss]

Keep adding liquid chlorine as needed and brush the pool to mix it in. Use the robot. Be careful using the pump as you can lose prime easily without suction from the skimmer.

 

[HermanTX]

I guess I could turn the filter on since the deep end still has water. The skimmer is already closed off, and I can just have water return through one set of returns while the water is below the skimmer and return jets.

I would not risk that. Also don’t want to risk wetting your repairs. I would just dump LC in the remaining water and brush it around to mix. Ok for it to sit but I would test it daily - just to ensure you keep some chlorine in it.

 

[ugadawgs311]

I would not risk that. Also don’t want to risk wetting your repairs. I would just dump LC in the remaining water and brush it around to mix. Ok for it to sit but I would test it daily - just to ensure you keep some chlorine in it.

I'll keep adding LC. Maybe about 2 cups or so since it's so shallow. It's kind of funny being so shallow, yet new algae is still blooming. That stuff is persistent!

 

[The Sarge]

Thanks for the responses, everyone! This is very helpful!

Looks like my local Home Depot has liquid chlorine for just under $9/gallon. It’s 10% sodium hypochlorite - will that work for my purposes? Sounds like I should plan on having quite a few on hand to get through the whole process.

What about other chemicals? Or is this step mainly just a heavy purge with chlorine to nuke the algae?

Walmart has chlorine for about $5.50 a gallon. Home Depot and Lowes are $8-$9.

 

[ugadawgs311]

Update: The steps were repaired on 4/20, and I was told to wait 8 dry details before refilling. It's rained the past 2 days, so I'll likely refill the pool on 5/1 then being the SLAM process. My steps are:

1. Refill pool to desired level (about halfway up skimmer opening). Turn on pump and let water circulate for an hour or two (maybe overnight).
2. Test PH - adjust to achieve 7.2 ppm (will likely need muriatic acid to lower).
3. Test CYA - adjust to achieve 30 ppm (likely by adding stabilizer). (This may be unnecessary since my CYA was around 60 before the drain/refill.)
4. Test CH, TA, FC, and CC. Using PoolMath, add LC to achieve 12 FC level. This will likely require about 3 gallons of LC.
5. Check water roughly every 4 hours and add LC to maintain FC level of 12 until SLAM is complete. SLAM is complete when: CC is 0.5 or lower, I pass an Overnight Chlorine Loss Test, and pool water is crystal clear with no visible sign of algae (dead or alive) on floor and walls.

I'll also keep an eye on CH and TA throughout the process, but those levels should be ok based on my tap water tests. Am I missing anything? I'm looking forward to getting the pool refilled, crystal clear, and swimmable again!

 

[Mdragger88]

Update: The steps were repaired on 4/20, and I was told to wait 8 dry details before refilling. It's rained the past 2 days, so I'll likely refill the pool on 5/1 then being the SLAM process. My steps are:

1. Refill pool to desired level (about halfway up skimmer opening). Turn on pump and let water circulate for an hour or two (maybe overnight).
2. Test PH - adjust to achieve 7.2 ppm (will likely need muriatic acid to lower).
3. Test CYA - adjust to achieve 30 ppm (likely by adding stabilizer). (This may be unnecessary since my CYA was around 60 before the drain/refill.)
4. Test CH, TA, FC, and CC. Using PoolMath, add LC to achieve 12 FC level. This will likely require about 3 gallons of LC.
5. Check water roughly every 4 hours and add LC to maintain FC level of 12 until SLAM is complete. SLAM is complete when: CC is 0.5 or lower, I pass an Overnight Chlorine Loss Test, and pool water is crystal clear with no visible sign of algae (dead or alive) on floor and walls.

I'll also keep an eye on CH and TA throughout the process, but those levels should be ok based on my tap water tests. Am I missing anything? I'm looking forward to getting the pool refilled, crystal clear, and swimmable again!

It looks like you’re ready for
SLAM Process time
During the slam process only worry about fc & cc testing.
You’re an A+ student !

 

[ugadawgs311]

It looks like you’re ready for
SLAM Process time
During the slam process only worry about fc & cc testing.
You’re an A+ student !

Thank you! It's all due to the great help I've gotten here. Thank you, everyone!

 

[HermanTX]

Update: The steps were repaired on 4/20, and I was told to wait 8 dry details before refilling. It's rained the past 2 days, so I'll likely refill the pool on 5/1 then being the SLAM process. My steps are:

1. Refill pool to desired level (about halfway up skimmer opening). Turn on pump and let water circulate for an hour or two (maybe overnight).
2. Test PH - adjust to achieve 7.2 ppm (will likely need muriatic acid to lower).
3. Test CYA - adjust to achieve 30 ppm (likely by adding stabilizer). (This may be unnecessary since my CYA was around 60 before the drain/refill.)
4. Test CH, TA, FC, and CC. Using PoolMath, add LC to achieve 12 FC level. This will likely require about 3 gallons of LC.
5. Check water roughly every 4 hours and add LC to maintain FC level of 12 until SLAM is complete. SLAM is complete when: CC is 0.5 or lower, I pass an Overnight Chlorine Loss Test, and pool water is crystal clear with no visible sign of algae (dead or alive) on floor and walls.

I'll also keep an eye on CH and TA throughout the process, but those levels should be ok based on my tap water tests. Am I missing anything? I'm looking forward to getting the pool refilled, crystal clear, and swimmable again!

Great overview and plan. you got this!!!!
Post your test results after you fill the pool and before you add anything.
You are correct that your CYA may be close to your desired level needed for the SLAM but testing will confirm It.

 

[ugadawgs311]

Update: Pool is now refilled (took about 19 hours and 15 minutes)! I ran a water test this morning. Here are the results:

• Free Chlorine: 1.5ppm
• Combined Chlorine: 0 (or very near 0).
• PH: 7.8-8.0ppm
  • Acid Test: took 2 drops of R-0005 reagent to lower reading to 7.2ppm.
• Total Alkalinity: 60-70ppm
• Calcium Hardness: 90ppm
• Cyanuric Acid: just above 30ppm.

So, is first step to lower PH to 7.2ppm? Should I do that before adding any LC?

I don't think I need to touch CYA since it's right at 30ppm. Based on the CYA level, I need to add about 3 gallons (maybe slightly less since FC is already at 1.5ppm) of LC to achieve FC level of 12ppm (it's been said that 1 gallon LC will increase FC by about 4ppm - how did you all figure this out? Is there an online calculator for this?).

I'll continue testing the water approximately every 4 hours to maintain the FC level of 12ppm, and hopefully the water will clear up soon. Thanks for all the help!

 

[HermanTX]

First I want to ensure we have the right CYA. You mention "just above 30" so we always round up so your CYA was 40. Could you see the dot at 40 and not at 30? If so then it is 40 which implies a FC for SLAM of 16ppm

We all use the
PoolMath app. It helps determine amount of chemical based on pool size. Do you have it?