Has anyone succeeded at shocking a green pool without using the pump to circulate?

[PoolDoc]

*If* you kill it,
*And* you have no circulation,
*Then* it will tend to settle out over a few days time.

What is the goal here? Are you wanting to get a head start on summer? Avoid having the slime 'eat' your stabilizer? Those are possible, though it may already be too late for the second.

Or, do you want your pool to look nicer, even though your pump is not running? That is pretty iffy. Floc -- alum -- might help, or you might make a mess. Poly aluminum chloride, in a number of the liquid flocs, is easier to work with (ie, less likely to make a huge mess), but it's no slam dunk.

It's your pool, so you can do as you like. If you do decide to use floc, follow the directions VERY carefully. And make very sure the algae is DEAD first. Nothing flocs live algae.

[etbrown4]

The goal is to have pool water clear enough to dye test 4-5 vertical cracks in the top 24" of the pool. I've drained the Present water level down 30".

Right now the water is somewhat green - I'd say a mild case, but upon filling up the pool, adding to what's in there now, I don;t think I'll be able to see through the water well enough to do the dye tests.

So, if I could find a way to shock the water in the pool now, and get it mostly clear - then my hope was to have clear enough water, upon filling, to do the dye tests.

If dead algae does drop to the bottom, if left alone, I don't know. That's where I thought the Flock might help. However, if the water is likely to still be murky then I still won't be able to see through it.

[PoolDoc]

If you kill the algae, FIRST, and then fill slowly, using a bucket or trashcan to avoid circulation, you can probably get the water clear enough.

However, I don't see how you'll be able to avoid stirring up what's on the bottom, when you are in the pool leak testing.

But, you STILL don't want to use floc -- it produces a fluffy bottom mess that has to be VERY carefully vacuumed up. It would be substantially more likely to be 'stirred up' than if the algae will settle on its own.

[etbrown4]

Is it ok just to add a pound of shock per 10,000 gals, or must you do algecide too. It seems as if many pros do it one way and many do it another.

This particular pool water is what I would call light green in color, and I've seen some far worse! I.E. you can barely see the bottom.

[Watermom]

You don't need algaecide to kill algae. Algaecide is a much better as a preventative than it is at actually killing algae. To kill algae, you just need chlorine.

What kind of shock are you planning to use? Any idea what your CYA level is?

[etbrown4]

Don't know about the CYA.
On the chlorine, I planned to use the 1 lb packs from Lowes. I think it said the active ingredient was 53% but can't remember exactly what it was. Would that make a difference?

[Watermom]

Any form of chlorine can kill algae. I don't know what the 1 lb. packs from Lowe's are, but I suspect they are dichlor. All pools need some CYA but when it gets too high, then you need to keep your chlorine levels higher and higher in order to keep algae at bay. Some forms of chlorine are stabilized which means they have CYA (cyanuric acid) in them. Trichlor tabs (like what you put in a chlorine feeder) and dichlor powder are both stabilized.

Many people are not aware of the connection between CYA and needed chlorine levels. They use stabilized forms of chlorine for long periods of time and then don't keep their chlorine levels where they need them and then end up with algae. We see this all the time -- people who have algae and can't figure out why.

The reason I asked if you knew your CYA level is because if you knew that your CYA level was already high, I was going to recommend against using dichlor shock and instead using either bleach or pool store liquid chlorine (which is the same ingredient as bleach at a higher level and usually a MUCH higher price!)

You can read more about the CYA and chlorine connection in the Best Guess Chlorine Chart in my signature below.

EDIT to add that some pools (not all) lose all their CYA over the winter anyways so it may not matter.

[etbrown4]

Don't know about the CYA.

I planned to use some Shock bought at Lowes. Says 53% Sodium Dichloro triaz something.

What ingredient should I be looking for?

[PoolDoc]

Dichlor is fine - given cold water, you'll need to pre-dissolve it, to keep it from sitting on the bottom.

The problem is the 53% . . . if it's 53% available chlorine, you're OK. If it's 53% dichlor + 47% other stuff, not so good. Some of the other stuff they blend with, is not what you want to put in your pool. If you can tell us brand and EXACT product name, we can probably find out.