Draining Pool and Starting Over

[rads2525]

So after a long period of unemployment, and recently getting a job, I’d hoped to save my pool from having been a bog. Got it blue for a while but it was always cloudy and after finally using HTH green to blue (which I shouldn’t have since I have a single Hayward cartridge and not a backwash system), all the dark green algae is settled at the bottom of the pool and my Polaris robot and my laughably small manual vaccum fills up after only 2 minutes.

It’s a (approximate) 18,000 gallon in ground gunite pool with chlorinated water and I’ve been told by professionals I’ll need to drain it entirely do an acid wash and then refill. I don’t have $800 for this. What can I do to start over? Is it really a risk to a gunite pool to drain in its entirety since “empty boats float?” If it cracks I’m done, I’m not fixing it. Maintaining this pool has been a real struggle even with a top tier test kit I just bought. It’s always losing chlorine and evaporating and my cya was 80 last week and somehow even higher this week lol (with 0 free chlorine). Pine needles fuming into my pool from a neighbor usually creates this issue of blue to green overnight I think this is the last summer I have this pool so I would love to use it at least once more before it gets cold here in Dallas. We’ve also been switching out the filters and washing them daily (or I just buy a new one).

Whatever I can do to ameliorate the cost and start over myself would be great but I still need a better system to get all this algae gunk off the pool floor. We have a small sump pump but I might need to rent something more powerful for the gunk.

Thank you!!

 

[Bperry]

So after a long period of unemployment, and recently getting a job, I’d hoped to save my pool from having been a bog. Got it blue for a while but it was always cloudy and after finally using HTH green to blue (which I shouldn’t have since I have a single Hayward cartridge and not a backwash system), all the dark green algae is settled at the bottom of the pool and my Polaris robot and my laughably small manual vaccum fills up after only 2 minutes.

It’s a (approximate) 18,000 gallon in ground gunite pool with chlorinated water and I’ve been told by professionals I’ll need to drain it entirely do an acid wash and then refill. I don’t have $800 for this. What can I do to start over? Is it really a risk to a gunite pool to drain in its entirety since “empty boats float?” If it cracks I’m done, I’m not fixing it. Maintaining this pool has been a real struggle even with a top tier test kit I just bought. It’s always losing chlorine and evaporating and my cya was 80 last week and somehow even higher this week lol (with 0 free chlorine). Pine needles fuming into my pool from a neighbor usually creates this issue of blue to green overnight I think this is the last summer I have this pool so I would love to use it at least once more before it gets cold here in Dallas. We’ve also been switching out the filters and washing them daily (or I just buy a new one).

Whatever I can do to ameliorate the cost and start over myself would be great but I still need a better system to get all this algae gunk off the pool floor. We have a small sump pump but I might need to rent something more powerful for the gunk.

Thank you!!

Welcome!

It depends. You mentioned some financial constraints and that’s one of the decision makers between draining and clearing up the current water.

But I’d first warn you to figure out how to maintain it once it’s clear no matter how you do it. If you plan to use TFP, you’ll need one of the two test kits we endorse. The TF-100 is highly recommended if you don’t already have it. To stay algae free, you need to commit to maintaining the chlorine/CYA ratio in this chart, which is always dependent on how much CYA is in your water.

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

If you want to save the water you need to SLAM the pool using this method:

SLAM - Shock Level and Maintain

We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.

www.troublefreepool.com

I’ll warn you with a pool that green it may take a lot of chlorine which might be more expensive than water but I doubt $800. I filled my 27k pool for about $250 so if yours would be $800 it might be cheaper to clear it. I’ll warn you to stay away from the pool store and get your chlorine from Walmart/hardware store. Pool store is the most expensive place to buy stuff that’s cheaper most everywhere else.

 

[rads2525]

Welcome!

It depends. You mentioned some financial constraints and that’s one of the decision makers between draining and clearing up the current water.

But I’d first warn you to figure out how to maintain it once it’s clear no matter how you do it. If you plan to use TFP, you’ll need one of the two test kits we endorse. The TF-100 is highly recommended if you don’t already have it. To stay algae free, you need to commit to maintaining the chlorine/CYA ratio in this chart, which is always dependent on how much CYA is in your water.

The Free Chlorine and Cyanuric Acid Relationship

Managing your cyanuric acid and Free Chlorine levels is key to stabilizing your pool. Learn how these two items affect each other.

www.troublefreepool.com

If you want to save the water you need to SLAM the pool using this method:

SLAM - Shock Level and Maintain

We’ve all had to deal with a green pool. Clear algae from your pool with a SLAM! Read here to use shock level and maintain to clear your pool.

www.troublefreepool.com

I’ll warn you with a pool that green it may take a lot of chlorine which might be more expensive than water but I doubt $800. I filled my 27k pool for about $250 so if yours would be $800 it might be cheaper to clear it. I’ll warn you to stay away from the pool store and get your chlorine from Walmart/hardware store. Pool store is the most expensive place to buy stuff that’s cheaper most everywhere else.

I just calculated that I’ve already spent well over that since late June when I got a warning from the city about how dark green my pool was (before I drained it half way after testing it and seeing the calcium hardness was way too high) and now. That’s why it’s so frustrating to be (almost) back where I was. It was blue just last week but I had no visibility to the bottom. I’ve literally spent any spare money on chlorine only to realize that all along, the algae at the bottom of the pool is piling up.

I just got the TF Pro test kit, my cya was always low until suddenly it shot up to 80/90 after using liquid chlorine instead of granules. The biggest frustration is not being able to get all the algae from the bottom. Before it was so cloudy I couldn’t see but now I can see it all on the bottom of the pool and the vaccum I bought is laughable. I’ve spent so much money trying to do it myself, using the Pool Math app (or Orenda) adding chlorine every day, switching out the cartridge filter (I don’t have the money to upgrade this), but without the ability to actually vaccuum the algae out, I’m just throwing money away. In the end, the money I spent on chemicals, including gallons and gallons of chlorine from Lowe’s or Walmart, shock (at first cal hypo and then switching to dichlor), cya, sodium bicarbonate, etc. plus the vaccuum, stainless steel brushes for all the residue on the sides, etc, probably approaches over $800 by now and to just spend the money on a green to clean is painful. All the professionals seeing how green my pool is and the dark bottom say it’s green and black algae, you need to drain and start over.

 

[Bperry]

I just calculated that I’ve already spent well over that since late June when I got a warning from the city about how dark green my pool was (before I drained it half way after testing it and seeing the calcium hardness was way too high) and now. That’s why it’s so frustrating to be (almost) back where I was. It was blue just last week but I had no visibility to the bottom. I’ve literally spent any spare money on chlorine only to realize that all along, the algae at the bottom of the pool is piling up.

I just got the TF Pro test kit, my cya was always low until suddenly it shot up to 80/90 after using liquid chlorine instead of granules. The biggest frustration is not being able to get all the algae from the bottom. Before it was so cloudy I couldn’t see but now I can see it all on the bottom of the pool and the vaccum I bought is laughable. I’ve spent so much money trying to do it myself, using the Pool Math app (or Orenda) adding chlorine every day, switching out the cartridge filter (I don’t have the money to upgrade this), but without the ability to actually vaccuum the algae out, I’m just throwing money away. In the end, the money I spent on chemicals, including gallons and gallons of chlorine from Lowe’s or Walmart, shock (at first cal hypo and then switching to dichlor), cya, sodium bicarbonate, etc. plus the vaccuum, stainless steel brushes for all the residue on the sides, etc, probably approaches over $800 by now and to just spend the money on a green to clean is painful. All the professionals seeing how green my pool is and the dark bottom say it’s green and black algae, you need to drain and start over.

If you have a skimmer, you can vacuum. The only issue is whether you can vacuum to waste or not. There are some mobile vacuum services you might try.

I will say though that adding liquid chlorine does not increase CYA. It’s the granular stuff that can contain it or they contain calcium which you want neither of to build up. You don’t need sodium bicarbonate.

But once the pool is back up and running, you need to add chlorine every day or two. The sun degrades the chlorine every day and if you don’t replenish it you eventually get the swamp. But you gotta figure out when to cut your losses and start over as well.

 

[rads2525]

If you have a skimmer, you can vacuum. The only issue is whether you can vacuum to waste or not. There are some mobile vacuum services you might try.

I will say though that adding liquid chlorine does not increase CYA. It’s the granular stuff that can contain it or they contain calcium which you want neither of to build up. You don’t need sodium bicarbonate.

But once the pool is back up and running, you need to add chlorine every day or two. The sun degrades the chlorine every day and if you don’t replenish it you eventually get the swamp. But you gotta figure out when to cut your losses and start over as well.

How do you vaccum via the skimmer? I have been looking for a valve through which to do this as it would be so much easier than using a manual vacuum. I see the main drain at the bottom of the pool but apart from the valve that attaches to my Polaris robot, I don’t see another one. Or is it through the actual skimmer basket? We plan to drain the pool at least halfway and then scrub the walls. The odd part to this is yes it’s green but unlike before when it was blue and very cloudy, now I can see to the bottom! It’s clear but green lol.

 

[Bperry]

How do you vaccum via the skimmer? I have been looking for a valve through which to do this as it would be so much easier than using a manual vacuum. I see the main drain at the bottom of the pool but apart from the valve that attaches to my Polaris robot, I don’t see another one. Or is it through the actual skimmer basket? We plan to drain the pool at least halfway and then scrub the walls. The odd part to this is yes it’s green but unlike before when it was blue and very cloudy, now I can see to the bottom! It’s clear but green lol.

You literally push a hose onto the hole in the skimmer and a pole mounted vacuum head goes on the other end. Anything that gets sucked up will go to the filter though so it’s not always advised. Maybe post a picture of your equipment pad and we can advise if there’s a waste valve.
.

The Polaris won’t clean up algae, just big chunks of stuff that sank.

 

[HermanTX]

We plan to drain the pool at least halfway and then scrub the walls. The odd part to this is yes it’s green but unlike before when it was blue and very cloudy, now I can see to the bottom! It’s clear but green lol.

What is the plan to partially drain the pool? Do you plan to use sump pump? Show photos from different angles of your equipment pad to help determine if there is another way to drain.

 

[rads2525]

What is the plan to partially drain the pool? Do you plan to use sump pump? Show photos from different angles of your equipment pad to help determine if there is another way to drain.

I plan to use the vacuum a bit although the bag is so small but yes I have this small sump pump I used to last time to partially drain. I also took pics of some valves I see along the side of the pool under the water. I cannot see the main drain at the deepest part of the pool. The skimmer basket is full of what looks like algae or sediment. I am using skimmer socks now so that when I pull the basket up, all that nastiness doesn’t just float back into the pool. In one of the pics I circled the connection for the Polaris pump and a valve to its left that I’m not what it is.

 

[rads2525]

What is the plan to partially drain the pool? Do you plan to use sump pump? Show photos from different angles of your equipment pad to help determine if there is another way to drain.

I was also just able to vacuum this little spot with my small little vacuum after 2 minutes. Had to pull it out to empty the bag which is algae water but it shows it is possible but it might be easier if I drain so I can also scrub the sides of the pool that have a film on it.

 

[reggiehammond]

It's very, very dry in DFW area, so ground water is not going to be a major concern. I'd wait a few more days for heat to break some, then I'd dump as much as you can, then refill as fast as you can. Starting with mostly fresh water will shorten duration of SLAM and reduce the amount of chlorine needed. This is actually the time of year where liquid chlorine starts to disappear from Wal-mart, HD, etc.

Lack of chlorine causes algae-infested pools. TFP methods are simply about making sure your FC (free chlorine) never falls below the minimum. Pool care can be very simple, but many people make it seem very hard.

FC/CYA Levels
Pool Care Basics
SLAM Process

 

[HermanTX]

I was also just able to vacuum this little spot with my small little vacuum after 2 minutes. Had to pull it out to empty the bag which is algae water but it shows it is possible but it might be easier if I drain so I can also scrub the sides of the pool that have a film on it.

If you brush the walls and drain using the sump pump you will remove some of the algae to make it easier to clean up.

 

[rads2525]

If you brush the walls and drain using the sump pump you will remove some of the algae to make it easier to clean up.

How much more should I drain? And I’m brushing but this algae is not coming off the sides. I’ve vacuumed and skimmed with a fine mesh skimmer so I’ve opened more of the floor or the pool. Should I try to drain all the way and get someone in here to do an acid wash to start over? I have some liquid chlorine and a watering can. Pour along the sides and brush with a stainless steel brush?

 

[Bperry]

How much more should I drain? And I’m brushing but this algae is not coming off the sides. I’ve vacuumed and skimmed with a fine mesh skimmer so I’ve opened more of the floor or the pool. Should I try to drain all the way and get someone in here to do an acid wash to start over? I have some liquid chlorine and a watering can. Pour along the sides and brush with a stainless steel brush?

You just need to follow the SLAM process. Brushing and filtering is great but those don’t kill algae. Chlorine is really your first priority if you are trying to save the water. Wall stains and other stuff is addressed after you have clean water.

 

[HermanTX]

How much more should I drain? And I’m brushing but this algae is not coming off the sides. I’ve vacuumed and skimmed with a fine mesh skimmer so I’ve opened more of the floor or the pool. Should I try to drain all the way and get someone in here to do an acid wash to start over? I have some liquid chlorine and a watering can. Pour along the sides and brush with a stainless steel brush?

I would not do the acid wash. You indicated your budget was tight and that still will not rid your pool of algae. Chlorine kills algae.
Also, dealing with acid requires some additional safety precautions plus a lot of acid.

As indicated before, it is very hot there so you want to limit the plaster exposure to the sun. I would drain no more than 75% of the pool. Brush the sides and bottom the best you can to loosing up any algae to be pumped out. You will not get it all but that is OK.
Start to fill your pool immediately once you stop pumping water out. Add a couple of gallons liquid chlorine as you fill. That should raise FC to about 11ppm. Then test your CYA. We need CYA at 30ppm (minimum) for a SLAM. You have never told us what your current CYA test value was. But it will be reduced now with the draining.

Buy more liquid chlorine as you will need that and have some acid on hand to adjust pH if needed. That, and stabilizer, if needed to increase CYA, is all you need.

Keep us informed.

 

[rads2525]

You just need to follow the SLAM process. Brushing and filtering is great but those don’t kill algae. Chlorine is really your first priority if you are trying to save the water. Wall stains and other stuff is addressed after you have clean water.

Ok thank you but I was told that I could use all the liquid chlorine in the world on this pool (and I have in recent weeks), if the dark algae at the bottom of this pool isn’t vacuumed out, it won’t matter. I would put a few gallons in every night and get my total chlorine up to 5ppm, water was bluish, but the next day, it would be back to green. Chlorine was never able to get high enough to reach SLAM levels. I was spending $70 every other day on 8 gallons of liquid chlorine only for me to test the next day and free chlorine would be 0 when total
Chlorine was 5?? People on the other pool forums said I was wasting chemicals and chlorine trying to SLAM if I couldn’t vacuum out the waste so that’s why I’m frustrated.

Whenever I tested my pool, ph and alk were a bit low (7.1 and 70), total chlorine hovered between 3-5ppm (despite putting 6 gallons of liquid chlorine in the night before per the SLAM recommendation on the pool math app), and my CYA was nonexistent. Then suddenly my CYA per a Leslie’s test said 180. I had no idea how that happened. In fact we stopped using stabilizing tablets for our floater. After I got the TF pro test kit, cya was a more reasonable number 80. The next day it climbed to 90. That was my last cya reading before I began draining. My main issue has been I use a ton of chlorine per the SLAM process and it may be killing the algae but I cannot filter it out well enough for a clear pool good enough to swim in.

I’ll drain a bit more tonight and then start refilling tomorrow.

 

[HermanTX]

Ok thank you but I was told that I could use all the liquid chlorine in the world on this pool (and I have in recent weeks), if the dark algae at the bottom of this pool isn’t vacuumed out, it won’t matter. I would put a few gallons in every night and get my total chlorine up to 5ppm, water was bluish, but the next day, it would be back to green. Chlorine was never able to get high enough to reach SLAM levels. I was spending $70 every other day on 8 gallons of liquid chlorine only for me to test the next day and free chlorine would be 0 when total
Chlorine was 5?? People on the other pool forums said I was wasting chemicals and chlorine trying to SLAM if I couldn’t vacuum out the waste so that’s why I’m frustrated.

Agree that once algae is dead, it does need to be removed from the pool. That is normally done through filtering or via vacuum to waste or in your case, some can be removed as you drain the pool.
What size filter do you have (need model number or size in terms of sq. Ft.. As you filter out the algae, it will require to clean the filter more often.

I sense that you are not following the SLAM Process per the document. If you had a CYA of 90 then the SLAM level would need to be 36ppm and it is important to MAINTAIN (the M in SLAM) that level throughout the day. Live algae will start to be consumed which lowers the FC within hours after it is added. It is important to test every 2-3 hours when you first start the SLAM to keep the FC up.

So when you start to refill the pool, test your CYA, hopefully it will be around 30ppm. If lower, you will need to add stabilizer to get it back to 30 to start a SLAM.

Also, clean your filter before you start the SLAM, maybe while you are draining the pool now.

 

[Bperry]

Ok thank you but I was told that I could use all the liquid chlorine in the world on this pool (and I have in recent weeks), if the dark algae at the bottom of this pool isn’t vacuumed out, it won’t matter. I would put a few gallons in every night and get my total chlorine up to 5ppm, water was bluish, but the next day, it would be back to green

This is why you need the TFP test kit. Total chlorine is a useless number. You need to know free chlorine (FC) and combined chlorine (CC). Note that Total chlorine (TC) is just a math addition of FC+CC=TC. So a FC of zero and CC of 5 would be TC=5. That’s a terrible situation no matter the CYA level. But a FC of 5 and a CC of zero is great as long as the CYA is lower than ~50ppm.

. Chlorine was never able to get high enough to reach SLAM levels. I was spending $70 every other day on 8 gallons of liquid chlorine only for me to test the next day and free chlorine would be 0 when total
Chlorine was 5??

Yep, that means the FC chlorine was depleted killing stuff (turned into CC) and you needed more chlorine to keep going.

People on the other pool forums said I was wasting chemicals and chlorine trying to SLAM if I couldn’t vacuum out the waste so that’s why I’m frustrated.

Whenever I tested my pool, ph and alk were a bit low (7.1 and 70), total chlorine hovered between 3-5ppm (despite putting 6 gallons of liquid chlorine in the night before per the SLAM recommendation on the pool math app), and my CYA was nonexistent. Then suddenly my CYA per a Leslie’s test said 180. I had no idea how that happened. In fact we stopped using stabilizing tablets for our floater. After I got the TF pro test kit, cya was a more reasonable number 80. The next day it climbed to 90. That was my last cya reading before I began draining. My main issue has been I use a ton of chlorine per the SLAM process and it may be killing the algae but I cannot filter it out well enough for a clear pool good enough to swim in.

I’ll drain a bit more tonight and then start refilling tomorrow.

The Leslie’s tests are a joke. Don’t waste time/money going there.

You do need to vacuum out anything on the bottom if possible. But simply vacuuming it out isn’t going to do all that much if you don’t maintain chlorine because the algae reproduce fast.

Note the TFP recommendations are not shared with other pool forums and so you can’t mix and match advice here and there and expect to be successful. The chlorine usage issue is why draining water was recommended. Water is nearly always cheaper than chlorine.

 

[rads2525]

Agree that once algae is dead, it does need to be removed from the pool. That is normally done through filtering or via vacuum to waste or in your case, some can be removed as you drain the pool.
What size filter do you have (need model number or size in terms of sq. Ft.. As you filter out the algae, it will require to clean the filter more often.

I sense that you are not following the SLAM Process per the document. If you had a CYA of 90 then the SLAM level would need to be 36ppm and it is important to MAINTAIN (the M in SLAM) that level throughout the day. Live algae will start to be consumed which lowers the FC within hours after it is added. It is important to test every 2-3 hours when you first start the SLAM to keep the FC up.

So when you start to refill the pool, test your CYA, hopefully it will be around 30ppm. If lower, you will need to add stabilizer to get it back to 30 to start a SLAM.

Also, clean your filter before you start the SLAM, maybe while you are draining the pool now.

I use the Clean and Clear Pentair Filter 200 sq ft. (PAP200). I have 3 of these that I rotate and clean but admittedly I wasn’t changing these out twice a day, maybe every day to every other day even though I was running the pump for at least 12 hours straight or when I’d first use shock, 24 hours.

Thank you. I am realizing that I was missing the M part and/or not testing as frequently as we should’ve after we did the initial blast. Or we were just testing chlorine (prior to getting the TF pro test kit) and reacting to the chlorine levels and not looking at cya at the same time. As I drain a bit more and vacuum, when I refill I will test. I will also take a deeper dive into this TF pro test kit. My son was testing for me but I need to test more often than he wants to especially since I bought the SLAM accessory for it. There were a lot of bells and whistles in this kit that I need to utilize.

 

[HermanTX]

I use the Clean and Clear Pentair Filter 200 sq ft. (PAP200). I have 3 of these that I rotate and clean but admittedly I wasn’t changing these out twice a day, maybe every day to every other day even though I was running the pump for at least 12 hours straight or when I’d first use shock, 24 hours.

Thank you. I am realizing that I was missing the M part and/or not testing as frequently as we should’ve after we did the initial blast. Or we were just testing chlorine (prior to getting the TF pro test kit) and reacting to the chlorine levels and not looking at cya at the same time. As I drain a bit more and vacuum, when I refill I will test. I will also take a deeper dive into this TF pro test kit. My son was testing for me but I need to test more often than he wants to especially since I bought the SLAM accessory for it. There were a lot of bells and whistles in this kit that I need to utilize.

OK great. That extra SLAM option for FC testing will be needed.
Once you fill, test for everything to have a starting baseline. This is as follows
pH
FC
CC
CH
TA
CYA

Print out and read the SLAM Process so you have a good understanding of it.
Stock up on liquid chlorine. 18,000 gals is a fairly large volume that needs to be treated.
Truthfully, that 200 sq ft filter is small, glad that you have multiple filters that you can switch out as needed.

 

[sande005]

About vacuuming:
You need: A vacuum head, a long pole, a hose for the head, and an adaptor that goes in your skimmer.
This Home Depot listing shows (more or less) the basic three (but not the adaptor). Not saying you should get this one, but Google and Amazon will give you an idea of the varieties to choose from. Pool Mate Deluxe Transparent Pool Vacuum Head K052BBX-PM - The Home Depot
There are many styles of each, and cost range. If you have the long pole for a brush or net, you can use that.
It sucks water from the head into the skimmer, as you move it to brush/scrub and suck things from the bottom/sides of the pool.
We can advise as to specifics, but it is easy for us to spend your money, so get an idea of what's out there and what your budget for it may be.

Before jumping in to it:
As asked before, post a picture of your equipment area (pump, filter, valves). Using the above vac can fill up your filter very quickly with the amount of algae you have. So, if there is a way to bypass the filter and just got the yucky stuff straight out of the pool, we can tell from the pictures. Many, but not all, pools have a valve to turn to do that.
Second - live (green) algae is really sticky! So it can be hard to scrub off. But, as you continue with the SLAM, and it gets killed, it turns into a fine powder that is easy to vacuum out. But it will be a process. So you likely will get very familiar with operating the vacuum.