One pool guy told me that Black algae is almost impossible to kill. Is it true?

NewB77777

Well-known member
Dec 1, 2019
80
Los Angeles
Two pool guy told me that they can remove it by using acid. and a guy in Leslie also told me to use acid to kill black algae.
I'm very confusing because I'm keep getting two totally different advices :)

How about to mix acid with water make it not too strong, and pour onto the black algae, and scrub.
Will it still damage plaster?

I tried to brush with chlorine. however it looks like it doesn't work well.
I want to try something strong, and it looks like professional pool guys use acid to remove black algae.
Do they use it because it will just make job done fast, and they don't care pool's life?
 
Last edited:

thomasandanita

Well-known member
Mar 14, 2019
103
willis texas
Bro, listen to what the people here are recommending for you.
You have asked them for help, they have given you excellent advice. By your own responses, you seem to be ignoring the recommendations.
The pool looks great now compared to what it did. Fill it with water, get elevated chlorine in it and get a test kit to confirm the results.
I don’t know everything about pools, but if I asked for advice here, I would follow it. The hdx chlorine from Home Depot is typically the cheapest around my area.
Best of luck.
 

JJ_Tex

Bronze Supporter
Jul 17, 2019
719
Prosper, TX (DFW)
LA literally has 100% chance of rain the next 2 days. Have you started filling it yet?

Properly chlorinated pool water will kill algae, including black algae. I'm sure acid will also kill algae, but it will also dissolve some of your plaster and shorten the lifespan. Seems like an easy choice to me.
 

NewB77777

Well-known member
Dec 1, 2019
80
Los Angeles
I was thinking it is good chance to kill black algae when it is empy
However I will stop thinking about acid.

So after filling water and good chemical will kill black algae(make black color gone), right?

BTW, is it ok water can go into the water light housing?
I took off to see inside and to clean it, and I found that there are insects and mud things, and there is no O ring to make it seal.
So it looks like water can be there easily.
 

Attachments

Last edited:

NewB77777

Well-known member
Dec 1, 2019
80
Los Angeles
It is normal for water to get behind the light. It is not normal for there to be water inside the metal light housing.
Yes water is behind the light. However it doesn't looks like water is inside the metal light housing.
However to prevent insects and debris to go behind of the light, I think it is better to seal.
Can you recommend the good way to do?
 

borjis

LifeTime Supporter
Aug 19, 2014
3,068
Pacific NW
Newb, the best advice going forward is to either follow our advice which seems like you are now, or follow
the pool store advice. The two cannot be mixed together. You could have made your plaster situation worse
by cleaning it with acid. You also drained your pool without a second thought, which could have popped out of the ground completely
destroying it. Nobody here would have recommended that.
 
  • Like
Reactions: NewB77777

NewB77777

Well-known member
Dec 1, 2019
80
Los Angeles
Newb, the best advice going forward is to either follow our advice which seems like you are now, or follow
the pool store advice. The two cannot be mixed together. You could have made your plaster situation worse
by cleaning it with acid. You also drained your pool without a second thought, which could have popped out of the ground completely
destroying it. Nobody here would have recommended that.
So, I'm watching the news and they are talking about the flooding rains that hit LA.

I'm scared to ask, but did you put water in the pool?
I started late.. so now only around 1/30 is filled.
I'm little worry about the possible pop up.
However I couldn't imagine that pool can pop up when I decided to drain:)

BTW, when I asked to local pool guys about the possible popping up.
They told me it is very very rare.
One guy told me he saw popped up pool just 2 times for 25 years.
And he told me that it was happen when there was earthquake.
I guess popping up happen rare in California because soil here is well drain..
I have found that some advices from those pool guy were not true.
So I'm not sure how rare popping up can be happen.

BTW, I'm going to purchase filters, and I found this.
Is this good?
 

mguzzy

Well-known member
Jul 8, 2015
927
OV, CA
Wow what an adventure...
-Acid will surely remove the algae.. it will also remove the plaster. So if you follow that course be prepared to patch the plaster if you do that. From the pics it looks like there is already some minor spalling of the plaster surface.
-The light niche (the thing in the pool wall) is designed to be filled with water, the enclosure (the thing you have on the deck) should be dry inside. There is no need to seal the enclosure into the niche
-I agree with everyone else.. get your pooled filled. one of the things that keeps a pool in the ground is the weight of the water in it. With the impending rain, there is a possibility the hydraulic pressure of the ground water on the empty pool could pop it out and then you'll have a bigger problem on your hands.
-my neighbor had a white plaster pool and a black algae infestation... I don't think they ever really got it under control. The staining was so bad the new owners had the pool re-plastered.
 
  • Like
Reactions: NewB77777

mguzzy

Well-known member
Jul 8, 2015
927
OV, CA
we posted at the same time...
yes pools popping out are rare events.. but no sense creating the perfect combination of conditions to increase the chances it will happen.

I couldn't tell from the pics, but your existing cartridges don't look too bad. Do you know how old they are? You can soak them in a solution of TSP to clean them.
 
  • Like
Reactions: NewB77777

NewB77777

Well-known member
Dec 1, 2019
80
Los Angeles
I think water will be full in couple of hours.
I ordered Taylor K-2006C, however it looks like that I can get it next week.
So I want to put some chemical in pool to prevent water change to green.

Can you let me know what to do?
Thanks.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
13,150
Northern NJ
I think water will be full in couple of hours.
I ordered Taylor K-2006C, however it looks like that I can get it next week.
So I want to put some chemical in pool to prevent water change to green.

Can you let me know what to do?
Thanks.
How many gallons in your pool?

Put in 5 ppm of liquid chlorine every day or two until you can test the water.

Add stabilizer using the sock method for CYA 30.

We use PoolMath to calculate dose based on pool gallons.
 
  • Like
Reactions: NewB77777

Rancho Cost-a-Lotta

Silver Supporter
Apr 10, 2018
1,052
Rancho Cucamonga, CA
NewB...if you plan to stick around and adopt the TFP method of pool care, now is a good time to complete your signature. Take a look at mine and others to help set up yours. Important now is pool volume and how you plan to chlorinate your pool. I didn't see a salt water chlorine generator (SWG) on your equipment pad, so I assume you will be using liquid chlorine. Solid forms of chlorine work, but using them on a daily basis come with side effects that will lead to frequent pool drains/refills. The TFP method requires daily testing and dosing of chlorine to be effective, particularly when the weather starts warming up. When you get to know the needs of your pool, you won't need to test every day. An SWG will negate the requirement to dose daily, but you'll still need to test frequently to control pH and to ensure your SWG is keeping up with chlorine demand.

Will you be caring for your pool? Will you be testing and dosing yourself? If so, all the info and advice is free...and it works. As mentioned earlier, pool store testing and advice don't play well with TFP.

For now, follow Allen's advice. If your pool is 20,000 gallons, a gallon of 10% bleach now and a quart per day will keep you in good shape until your test kit arrives. 5 lbs of CYA will get you to about 35. You can pick up CYA at Home Depot. It's sold as Chlorine Stabilizer.

If you're near my area, Mountain View Pool Supply off Carnelian and the 210 sells Hasa 12.5% chlorine.

Best of luck!
 
Last edited:

proavia

LifeTime Supporter
TFP Guide
Feb 6, 2015
1,677
Chandler AZ
Yes water is behind the light. However it doesn't looks like water is inside the metal light housing.
However to prevent insects and debris to go behind of the light, I think it is better to seal.
Can you recommend the good way to do?
Do not seal the light housing to the light niche. It is designed to allow water to circulate behind the housing to aid in cooling the housing when the light is on. The light can generate a lot of heat when on.

What you can do is to pop the housing out of the niche once or twice a year and clean out any debris. If cleaned on that frequency, chances are you won't find much debris behind the housing. I usually do mine the beginning of the season and end of the season (May and October here in the desert southwest).
 
  • Like
Reactions: NewB77777

NewB77777

Well-known member
Dec 1, 2019
80
Los Angeles
Do not seal the light housing to the light niche. It is designed to allow water to circulate behind the housing to aid in cooling the housing when the light is on. The light can generate a lot of heat when on.

What you can do is to pop the housing out of the niche once or twice a year and clean out any debris. If cleaned on that frequency, chances are you won't find much debris behind the housing. I usually do mine the beginning of the season and end of the season (May and October here in the desert southwest).
Thank you for all replies.
I try to do myself without hiring pool guy if it doesn't take too long and If I can save good money by doing it myself
Can you let me know how many hours(or minute) do I need to spend and the cost of all chemical monthly?
I can hire pool guy for about $90 monthly, and he will come every week to clean and maintain the chemical level.
So If I have to spend long time and have to spend $$ for chemical, then I think it is better to hire pool guy.

Regarding the light, Leslie's employee gave me wrong information then :)
He make me to buy a rubber O ring, and it seemed that it didn't fit well.
There is only one bolt between the metal light fixture and the housing, and it is not tight.
I remember it was tight before I took out the light fixture from the fixture.
Do you have any idea why it is not tight and how to fix?
I used same bolt.
I might have to buy right size rubber O ring.

I updated my signature.
Please check and let me know if I need to put more informations in there.
 
Last edited:

wogster

In The Industry
Apr 30, 2018
141
Toronto, Ontario, Canada
$90 a month, probably doesn't include the cost of the chemicals, which will have a significant mark up, they will also use some odd and expensive potions. The problem is that FC will drop by 2-3ppm per day, and needs to be at least 2-3 PPM, so if they guy comes once a week, you can be looking at a drop of as high as 21ppm. There are two possible solutions, pool guys use: shocking, which will raise the FC to say 25, then let it drop over the week, or using pucks, the problem with pucks is that they also add CYA. The FC will go away over the week, the CYA takes many months to go away. It's not uncommon to see a CYA, which should be between 30-50, end up 200 or more. This creates a problem, the higher the CYA the higher the FC needs to be, to work.

There are three of pool guy less solutions, manual chlorinating, chlorine pumps and Salt Water Chlorine Generators (SWCG), a chlorine pump, will pump liquid chlorine at either a constant or timed rate, to keep it at the optimum level. A SWCG will turn split sodium chloride into sodium and chlorine using electrolysis. As the chlorine is used, it recombines with the sodium, turning it back into salt. Of course a chemistry major can write 47 pages on the actual complex reactions, that take place, but effectively this is what happens. Manual chlorination requires no additional technology, you get home from work, test the chlorine level, dump in enough to bring it up to the maximum level in the range you want. For example your CYA indicates 3-8ppm, you test and get 4, so you add enough to get to 8. Confident that it will drop no more then 2-3 over the next 24 hours.