Dead Algae not filtering out?

Jul 12, 2010
145
Current water numbers. Chlorine 5+, pH 7.5, CYA 50, TA 130. I have not been able to find a test kit that goes above 5 on Chlorine.
Problem #2 – my sand filter is not filtering. I had a small algae problem in the beginning of the season and got it taken care of, but now I have this very fine, powdery stuff that collects on the bottom of the pool. It is green/brown. It always goes to the bottom of the pool and collects. I have found that it just goes straight through the sand filter and blows right back into the pool. In fact, each time I turn off the filter and then turn it back on, I get a big cloud of this green/brown stuff shooting out.
I removed all my sand, checked the laterals and all other pieces. No problems. Sand was ok. I dug it all out. And what I found was the sand on top was very clean. When I got to the bottom, the sand was saturated with green water.
My assumption is that I have dead algae that can not be filtered and keeps shooting into the pool.
I have left the filter on for a week and the pressure does not increase. The only solution I can think of it to vacuum to waste each day to get all the Crud off the bottom and keep letting the filter blow dead algae out until it all settles to the bottom of the pool.

Problem #1 – air is somehow leaking into my pump/filter system. I always see tiny air bubbles on the side of my pool and shooting out the jet. If you go underwater, you can see it as well. I can’t get the air bubbles to stop. When you look at the basket just before the super pump, there is always air at the top that can be seen through the clear plastic cover. I have also found that if I add said aid and the pressure goes up from 12 to about 20-22, all suction essentially stops when the basket in front of the super pump fills with mostly air. I see small amounts of water coming in, but more air is coming in so the basket never gets filled. I don’t know where the air is coming from. I see no leaks from the pipes above ground
 
Take a look at my sig and click the link for the test kits. Those will test much higher than 5ppm. They'll test up to 50ppm. You really need to get one to take control of your pool.

I'm not sure you've actually taken care of the algae problem you have. If it's still green it's not dead. A good test kit will let us figure out if you have taken care of it.

A very common place for air to get into the pump basket is the lid. Take it off and clean the surfaces and o-ring good then lube it with some silicon pool lube and put it back together. Inpsect the o-ring while you have it apart to make sure it's not nicked or broken.

Another common place to get air on the system is the skimmer. Check to make sure the weir operates freely and isn't sticking at any point. Also check to make sure there isn't a vortex being created in the skimmer. Raising the water level some might help that problem.
 
I also agree that I do not think you have killed the algae and need another treament of algaecide.
Make sure your ph is in the 7.4 to 7.6 range then shock the pool up to Chlorine to 5.
Then add your algaecide and keep filtering for another 24 hours.
Clean filter again.
 
It isn't dead, if it was dead it would be white. Sounds like mustard algae to me. Your description is exactly what it looks like and if it was regular green algae your 5ppm+ FC level would probably be killing it already.

First backwash and vac to waste to remove as much as you can. 5 ppm won't be enough to kill mustard and regular algeacide won't touch it. You will need to shock to a much higher level (20 ppm usually works for me, but the pool calculator recommends 29ppm for a CYA of 50). There are products made for mustard algae but personally I don't like them. Until you can get a high level test kit you can dilute your sample to test it, then multiply by the dilution rate (for example, mix 1/4 cup pool water with 3/4 cup tap water, text mixture, multiply result by 4)

As for the air in the basket, I agree with Bama
 
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Not starting anything but do not add more algaecide. What you need is good ole liquid chlorine. Algaecide is good at keeping algae from growing, but it isn't very good at killing it once it's started. And if you keep your FC levels right it's unnecessary.
I also disagree that it's mustard algae. Not enough info yet to say it isn't just the plain ole green variety.
The very first thing you need is a good test kit. Then we can start clearing this up for you.
 
To emphasize what bama just posted, don't get caught up in worrying about the type of algae.....I read where there are over 7,000 species of algae. Chlorine kills every one of them, so far.

The important thing to focus on is getting a good kit that will help you manage your water and then taking charge of your pool.

Because of the multiple issues you have, you may need to get a pool maintenance person to come visit. You cannot kill you algae with a system that has air leaks like you describe and they are difficult for a novice to find.
 
While chlorine does kill all types of algae, it takes at least twice as much to kill mustard algae than the regular green varieties. That is the only reason I differentiate, because typically recommended shock levels won't touch the stuff.

I can't say for sure whether it is mustard algae, dirt or some other substance, but his description matches and if he has been maintaining 5+ chlorine, shouldn't the green algae be dead already? I agree with Bama to nix the algeacide and stick with Chlorine, and to order a good test kit, but I wouldn't wait for it to arrive, because it can take over the pool pretty fast.
 
Thank you all for the advice.
I have been debating on whether to get a pool maintenance guy to come look at the pool or not. I think I need to now to look for air leaks. I have already done everything suggested with the basket lid as well as at the skimmer. My pool level is high enough. No eddies at the skimmer. No leaks that I can see.
Do any of you have advice on how to get a good one? I was thinking about using one of the local pool supply chains that also builds pools.
 
OK,
I think I am finally coming around here. I am not convinced I have an algae problem. I know, I know, you told me that all along.
Now my question is, if I get my chlorine level up to 20-30, how long do I need to keep it there?
Also, as far as swimming in the pool, what do chlorine levels have to be at in order for it to be safe to swim after all the shocking?
I want to make sure I get all the algae killed. I am worried that I will get it to where it looks all clear, then when I let my chlorine drop back down to 5, it will come right back.
I have got my pool to where it looks somewhat clear, I shock with 2.5 gallons shock for my 25K pool, the chlorine is off the chart for 3 days (my test kit only goes to 5), I vacuum all the algae off the bottom and send it to waste, but after a few days of my cholorine being at 3-5ppm, it greens right back up.
 

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jordangregory said:
OK,
I think I am finally coming around here. I am not convinced I have an algae problem. I know, I know, you told me that all along.
Now my question is, if I get my chlorine level up to 20-30, how long do I need to keep it there?
Also, as far as swimming in the pool, what do chlorine levels have to be at in order for it to be safe to swim after all the shocking?
I want to make sure I get all the algae killed. I am worried that I will get it to where it looks all clear, then when I let my chlorine drop back down to 5, it will come right back.
I have got my pool to where it looks somewhat clear, I shock with 2.5 gallons shock for my 25K pool, the chlorine is off the chart for 3 days (my test kit only goes to 5), I vacuum all the algae off the bottom and send it to waste, but after a few days of my chlorine being at 3-5ppm, it greens right back up.

I think you really need to get a better test kit. Trust me - even if you get it cleaned up this time without it, someday you'll go on vacation and come back to a green pool, and you'll wish you had bought it when they told you to. (There's a reason I know that.)

Do you know for sure how much CYA is in your water? Finding out and fixing that number is what eventually solved most of our issues the first time out.

The rest of out problem was solved by scrubbing the whole pool down. According to one of the algae articles I read here, algae can have a slime coat that protects it from the chlorine. Unless you scrub it all away, it can and will come back.
 
Go back and reread how to shock your pool! Shocking is a process and not a one time splashing of chlorine in it. You MUST keep the FC at shock level until you lose no more than 1ppm FC overnight, have .5ppm CC's or less AND your pool is crystal clear if you don't have a FAS-DPD kit (which you don't)! Adding and testing FC as often as every hour.

Adding 2½ gallons of 12.5% liquid chlorine to a 25,000 gallon pool only brings the FC up by 12ppm. You have to know where you started to know if that got you to shock level.

Keep in mind that every time your FC drops below shock level you're losing ground and in essence have to start all over.
 
Thanks for the replys.
I have ordered a test kit. Unfortunately, it will not be here until Wednesday.
Right now I just have a good old total chlorine tester from Taylor. I am diluting the pool water with tap water as was instructed by another poster and below are my numbers:

This morning my TC = ~5 My pool has been at about ~5 for the last week
I added 2 gallons shock at 2pm and at 3pm TC was at ~8-12
I added another gallon at 3pm and TC went up to ~18-24
I know I need another test kid, but I want to do something that is not a waste of time until then. I know right now that reading those Dang shades of yellow is tough.
I am not sure how to know how much chlorine at add to move my numbers up by 1pp. It seems right now that 1 gallon does about 5ppm. Maybe.
Can't wait for the new test kit to arrive.
Pool is still green looking.
I still have stuff sitting on the bottom of the pool. I need to vacuum to waste.
 
Vacuuming to waste is a good thing to do if you can afford the water replacement.

Learn to use pool calc. It'll tell you how much bleach you need to add. Put your test numbers in the now column and your desired number in the target column and it'll tell you how much you need to add to get you there.
 
I am also trying to figure out where this algae came from. If i would normally keep FC at 3-7, wouldn't I always be getting this algae coming back?
I am not sure where it came from.
I have a hunch that is came from my pool's solar blanket. It seems that whenever I take this think off, it drops in some dirty water. Maybe the top is just an algae factory?
 
jordangregory said:
I am diluting the pool water with tap water as was instructed by another poster and below are my numbers:

Your tap water probably has chlorine in it. You might consider diluting with distilled or some other chlorine-free water.
 
I have well water. Shouldn't be any chlorine. But how much chlorine is in city water?
Also, I went to buy shock today and the local pool guy told me he thinks that I don't have algae. He thinks I have minerals precipitating out of the water. He thinks that if I use something called "suspend" that I can then be ok after filtering out the remaining precipitate. I told him I have been vacumming to waste for a week or two and the stuff keeps coming back to the bottom of my pool. He thinks since the stuff if powdery and settles to the bottom of the pool and looks like dirt until it is stirred up (at which point it looks light green), it can't be algae.
We will see what happens when I see the pool in the morning.
I have added a total of 5 gallons of shock during the day today and have my TC to a little over 20. I should get my new test kit on Wednesday.
I started shocking at 2pm today and the pool still looked as green as before at 7pm before I left for the night.
I am curious to see what it will look like in the morning.
 
I have posted pictures of the pool this morning in case that helps.
I added about 3 to 4 inches of water last night so I would have some to waste.
I found the Chlorine was about 6-9ppm. Not sure how acurate this is. I just added 5 parts well water to 1 part pool water. I was at about 1-2 when matching the yellow colors up. I multiplied that by 6 to come up with 6-9ppm.
http://www.twolveswaterpolo.com/images/pool/1.JPG
http://www.twolveswaterpolo.com/images/pool/2.JPG
http://www.twolveswaterpolo.com/images/pool/3.JPG
http://www.twolveswaterpolo.com/images/pool/4.JPG
http://www.twolveswaterpolo.com/images/pool/5.JPG

Picture 3 is a closeup of what is on the bottom. It is powdery and when stirred up, makes a big green mess
 
It looks like dirt but it's hard to tell. You need to maintain shocking until your TF-100 gets there so you can run an OCLT (overnight chlorine loss test). That will tell you for certain if it's organics or not.
 

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