use of Alum for algae

[joefog]

I had a terrible problem with brown/green algae. After using Leslie's "Green to Clean" the pool was still cloudy. The rep at Leslie's suggested that I use Alum. I tried the Alum almost 3 weeks ago and cannot get it out of the pool. I continually have white powder at the bottom of the pool that I cannot vacuum away. Also, my filter continues to push "white water" that leaves a white foam on the top of the pool. I cannot seem to get rid of this with vacuuming to waste, backwashing, rinsing, etc.

I am about to take the filter apart, put in new sand and see if that helps.

 

[Bama Rambler]

Welcome to TFP.

Post the info about your pool and equipment. Obviously you have a sand filter, but what size?

It's probably a waste of time and money to change the sand.
What's you're filter pressure?
How often do you have to backwash?
Did you follow the directions on the floc to a tee?

 

[joefog]

I have an 18x36 diver (average 6') so a total of 29,000 gallons. The pool is a vinyl liner that is 3 years old. The filter is a Hayward S200 with 200 lbs of sand that is about 4 or 5 years old (if not more). The pool opened a deep dark brown, then to green and now is blue. I can see the bottom on the shallow end but not in the deep end.

 

[joefog]

Didn't see the other questions till now:
1. I don't see any pressure on the tank. Installed a brand new gauge but it is not registering anything.
2. I am backwashing about 2 times a day trying to get the white out of the water and the foam off the top of the pool.
3. When using the alum, the only thing that might have happened is that due to the excessive heat and humidity, the alum sat on the bottom for about 4 days before I started the process to vacuum (but always to waste).

 

[Bama Rambler]

Can you post a full set of test results? I realize they're probably from the pool store, but post them anyway.

You really should get a good test kit.

What all have you tried to clear it up?
Have you tried a little DE in your sand filter?
By the way, that filter is really very small for that pool. It's probably going to take a good while to clear it up even if everything is perfect.

I'm not belittling but make sure the multiport is in filter and not recirc or something else. You should have some pressure on the gauge. Does water come out of the gauge port if you take the gauge off?

 

[joefog]

1. I have tried to vacuum to waste where there is white powder on the bottom.
2. I have replaced the gasket in the multiport valve.
3. I have changed the pressure gauge - and water does leak from the port if gauge is loose or not there.
4. I had water tested this morning:
bromine - 0
calcium hardness 120
total alkalinity 80
ph 7.0
copper - ok
iron - ok
total dissolved solids ok 500
temperature 80

I have used super shock and algaecide. I have tried water clarifier.

 

[Bama Rambler]

So this is a bromine pool?

The numbers don't look bad except for the bromime being zero.

 

[joefog]

On 7/10 the bromine level was 5. However, I have to keep on filling pool when the water level goes down from the vacuuming to waste. I do try to get the PH to 7.4 to 7.8 but have not worried too much about the other issues until the water is clear. I do use chlorine to shock the pool along with the bromine. I can always open the brominator if that will help.

 

[joefog]

any suggestions about why the gauge is not showing any pressure?

 

[Bama Rambler]

Bad gauge. As long as the water squirts out of the port forcefully when the gauge is off it should be reading something.