I'm doing ok... but I could be doing better (in terms of managing my CSI between summer & winter); how about you?

[Gary Davis]

You'll find it won't.

I tested it with about two and a half feet of half inch PVC pipe, and you're right. I worked out a technique of putting it in the water with my thumb tightly over the top and then when I let go it shot up a bit up out of the top of the tube and then I capped it with my thumb and angled it out of the water - but that's way too much work.

I like your idea better so now I know why the holes on both end!

You might be able to work the top well enough, blocking it with your thumb, but it won't be convenient, especially when bending over to get it down into the water. The bigger problems are: the water will tend to fall out of the bottom as you bring it out of the water,

At first almost all the water fell out the bottom until I learned to angle it out, like you might scoop water with a spoon, sort of.
It worked but you had to get even lower on the deck - but the whole point was to save my knees - so it's not worth it to "scoop" the deep water out that way.

I like your idea better.

and if your sample container has a narrow neck then you'll lose another chunk of water aiming the bottom of the pipe at the container (picture: the container in your left hand, your right hand 30" away, at the top of the pipe holding your thumb over the top, while trying to aim the 30" of pipe at the little opening in the container).

Good point! I only splashed the water on the deck as I had decided early on it wasn't working as well as I had hoped it would.

Yes, a smaller pipe would work, but 30" of 3/4" PVC is about the amount of water needed for a full suite of tests.

I agree. I used 1/2 inch PVC of about two and a half feet long - which didn't hold all that much water.

It fills a Leslie's water sample container perfectly (which is sized for the correct amount of water). With a smaller pipe, you'll need to dip at least twice.

Agreed on both counts. Better to go into a sample bottle directly, taking into account your hand is still on one end of a long pipe.

I've already worked all this out. The pic I posted is actually the prototype. I redesigned/replaced it with the "current model," based on trial and error. But be my guest if you want to do it again! Maybe you'll think of something I didn't.

I think your idea is grand. I'm working on my own stuff for turning a sump pump into a pool vacuum, but it's in the nascent stage as you can see by my prototype connections in the image below for going from the vacuum hose to a garden hose.

Otherwise:
- 30" @ 3/4" PVC
- top 3/4" cap with 1/2" hole drilled through it
- bottom 3/4" cap with 5/16" hole drilled through it

You can flip the pipe over to get two different flow rates, if you find one is too slow or too fast.

You don't need to glue the caps.

I like the parts list! Perfect.

 

[Dirk]

Thanks for that idea for getting the water deeper down.

I'm interested in how you make out with this effort. Based on nothing but intuition, I'm gunna say that trying to determine a pool's chemistry without first thoroughly circulating the water is at best going to be fairly inaccurate, and at worst a recipe for poorly maintained if not harmful water, due to badly over-dosing or under-dosing the required chemicals.

Though I suppose it's better than no testing at all. I take that back, you could actually make things worse by miscalculating dosages. Pardon my nay-saying. Just playing devil's advocate...

 

[Dirk]

I wrote that last post this afternoon, but I guess I didn't click Post. Please accept my thoughts in the spirit in which they were given. You know, a cranky old man that relishes torturing others!

Pool vacuum from sump pump? Love it. Do tell. Though that should warrant its own thread. My "dirkventions" are all over this forum, so I'm with ya brother, if you can make something out of nothing, and save some money, or time or effort.

 

[Dirk]

Agreed on both counts.

You can hold the pipe (straight up and down) between your two fingers, with the cap keeping the pipe from sliding through them, then easily plug the hole with your thumb. This will give you the maximum reach and minimize the stooping, which is what we're both after! Then when you pull it out of the water, just let it hang straight down. With the sample container in your other hand, bring it to the end of the pipe, rather than trying to move the pipe to the container. Let the bottom cap rest on the container to keep it in place. With the smaller hole on the bottom, you'll find it pretty easy to "hit the bullseye" without spilling much, if any.

Then ya gotta hide the pipe when you're done, instead of leaving it handy near the pool, 'cause your kids will try to brain each other with it! I learned that by trial and error, too!!

 

[Newdude]

Though I suppose it's better than no testing at all. I take that back, you could actually make things worse by miscalculating dosages

Huge +1.

It will make things way worse. Like drain the 3/4 of the pool from high CH / CYA (or salt for other pools) when all along you thought it was low.

 

[Newdude]

So I needed to drain some accumulation yesterday and I took a wrist deep and elbow deep sample. The top layer (left) was 0 FC and the elbow sample was 2 FC (right), confirmed with the fas/did test.



I closed well into November, with a FC in the teens. It's been covered and cold and likely is still much higher than the 2 tested at elbow deep. I wouldn't trust any readings to dose from until it's well mixed.

 

[duraleigh]

Pump running?

 

[Newdude]

Pump running?

My pump is put away for the winter, but OP isn't running his either so I was showing what a difference it can be with unmixed water.

We were concerned he was adding CYA/CH/salt to make up for dilution, but without mixing first.

 

[duraleigh]

Got it.

 

[Newdude]

*update because I was bored.

I went back and used a 8ft piece of electrical pvc to get a bottom sample. Err. I'm sure there was some cross contamination, but it was mostly bottom water. To disturb it all as little as possible I first took a surface sample about wrist deep. Then I went elbow deep and then took the bottom sample.

The comparator block proved what I was expecting....... double digit FC down below (left side) and single digit at elbow deep (right side)




The fas/dpd said 9.5 FC and 3 FC respectively, with 0 FC in the top sample.

My CH was only a 50 or 75 to start so it was already low and its pretty cloudy today so CYA won't be too accurate, so i tested the salt for another example.

Wrist deep was 600 ppm
Elbow deep was 1600 ppm
Bottom was 3000 ppm

I closed Nov 19th and have this much variance in 72 days / 2.4 months. There is no telling how this will all average out without mixing well. Please nobody dose from their winter tests without mixing, and mixing well at that. A submersible pump won't move the same water that the pool pump can, but will achieve the same results if given a little longer to stir it up.

 

[Dirk]

Way to go, Mr. Wizard! Good data.

 

[pjt]

Wrist deep was 600 ppm
Elbow deep was 1600 ppm
Bottom was 3000 ppm

Good data points. I'm amazed at the differences. Salt and FC were much higher in the deep end. I'm curious if pH, TA, CH and CYA follow the same pattern.

 

[mgtfp]

*update because I was bored.

I went back and used a 8ft piece of electrical pvc to get a bottom sample. Err. I'm sure there was some cross contamination, but it was mostly bottom water. To disturb it all as little as possible I first took a surface sample about wrist deep. Then I went elbow deep and then took the bottom sample.

The comparator block proved what I was expecting....... double digit FC down below (left side) and single digit at elbow deep (right side)

View attachment 471194


The fas/dpd said 9.5 FC and 3 FC respectively, with 0 FC in the top sample.

My CH was only a 50 or 75 to start so it was already low and its pretty cloudy today so CYA won't be too accurate, so i tested the salt for another example.

Wrist deep was 600 ppm
Elbow deep was 1600 ppm
Bottom was 3000 ppm

I closed Nov 19th and have this much variance in 72 days / 2.4 months. There is no telling how this will all average out without mixing well. Please nobody dose from their winter tests without mixing, and mixing well at that. A submersible pump won't move the same water that the pool pump can, but will achieve the same results if given a little longer to stir it up.

Love your work. Interesting results.

 

[Newdude]

I'm curious if pH, TA, CH and CYA follow the same pattern.

The PH was high at all 3, likely from residual concrete and paver dust runoff from the new patio. All that rain had a PH of around 5 and should have lowered me considerably, so that's the working theory.



TA was 60 like it was, with the rain being similar to what was there.

Ch and CYA would likely be similarly diluted/stratified with 0 in the rain water. Dosing any of them without a good mix would likely backfire.