350k gal community pool, thrown in the deep end...

[Ed McCarron]

At startup, even though we fired the pumps up to waste, a bit of nasty green debris oozed backwards out of the pool drains. Now I've got a cloudy greenish pool. I can still see the lane lines at 12', so it's not too bad...

No chemicals except hypochlorite added, feeding appx 50 gpd, free cl2 is getting up towards 10ppm. pH is around 7.4.

We open for the weekend in three days. My filter sand (9 years old) is scheduled to be replaced the following week (10 filters, 650 pounds of #20 silica per...)

Whats my best chance at much clearer water by Saturday? Not real keen on flocculant, no means to vacuum to waste easily. Clarifier? DE into the skimmers? Keep the cl2 up and be patient? My filter pressure did increase a pound overnight, so it's pulling something out...

Can I add DE to a skimmer and expect it to hit all ten filters? Flying blind here...

Help?

 

[RobbieH]

Filter sand does not go bad. There's likely no reason to replace it.

Can you please post a full set of test results?

 

[Leebo]

First and foremost......welcome to TFP!


Second off.....is this an indoor or outdoor pool? Are there any local or state rules you must follow or is this completely a private pool?

 

[tim5055]

The first thing I will point out is that our methods are directed at much smaller residential pools. Plus the fact that many states regulate how commercial pools must be maintained (I'm not sure what state "Glenolden" is in) may also be a limiting factor in what methods you are required to follow.

First, we almost never recommend replacing filter sand. It's already millions of years old and doesn't wear out. We just recommend deep cleaning the filter.

Floculant and clarifier are almost never on our suggest use list. Too many problems with both of them.

We base our pool care system on accurate testing and only adding what the pool needs, when it needs it. To do that you need your own accurate test kit. If you don't have a kit that measures stabilizer (CYA) and has a FAS/DPD chlorine test I would say you should order a TF100 and at least include the XL option. That will give you what you need while you are clearing the pool, and probably enough reagents for a couple of years normal use.

To clear the pool we recommend a procedure we call a SLAM which involves raising the chlorine to shock level and maintaining it there until the algae is entirely eradicated as evidenced by water testing through an Overnight FC Loss Test (OCLT).

Here are the instructions for the SLAM Process.

But, I have to repeat myself, commercial pools are a differetn animal and have regulations to follow that homeowners don't have.

 

[Ed McCarron]

Fair enough. Yes, we have to comply with local health codes, and have a testing lab test weekly and submit to the state.

The filter sand not wearing is a new thing to me, the local pool store insists it wears out.

Guess my main goal for the week is to get the fine particles out I fear are passing through the filters...

This is a freshly filled pool - two day old water. it's in direct sunlight. In southeastern PA. If algae is a problem already, we're in trouble. ?

I'll see about the next batch of test results.

I learned something already....

 

[tim5055]

Fair enough. Yes, we have to comply with local health codes, and have a testing lab test weekly and submit to the state.

The filter sand not wearing is a new thing to me, the local pool store insists it wears out.

Guess my main goal for the week is to get the fine particles out I fear are passing through the filters...

This is a freshly filled pool - two day old water. it's in direct sunlight. In southeastern PA. If algae is a problem already, we're in trouble. ��

I'll see about the next batch of test results.

I learned something already....

"the local pool store insists it wears out" They are being less than truthful or are sadly misinformed.

"nasty green debris oozed backwards out of the pool drains" That is algae. Following our methods unless we can prove through testing that it is dead and gone it is still there. Only two things consume chlorine in a pool, UV and organics (like algae). By testing the loss overnight we can prove if there is something unseen in the water.

 

[YippeeSkippy]

What kind of test kit do you use for the multiple tests you must be doing during the day? Please provide the test kit name/number if known.

 

[Ed McCarron]

"that is algae"

With a healthy dose of goose, er, leftovers thrown in for good measure. It's a popular rest stop apparently...

I'll read up on slam and go from there. ?

Thanks!

- - - Updated - - -

It's a Taylor dpd kit. I'll get the actual number... The guards test pH and free cl2, the local pool store tests to help us balance alkalinity, etc.

 

[tim5055]

"that is algae"

With a healthy dose of goose, er, leftovers thrown in for good measure. It's a popular rest stop apparently...

I'll read up on slam and go from there. ��

Thanks!

- - - Updated - - -

It's a Taylor dpd kit. I'll get the actual number... The guards test pH and free cl2, the local pool store tests to help us balance alkalinity, etc.

The Taylor DPD kit does not test high enough for chlorine to follow our methods, but again you may not be able to because of regulation. But the DPD kit also does not allow for the specificity of chlorine. It's a color match test which can be very subjective. We recommend the Taylor FAS/DPT test for chlorine testing because it has accuracy to .2 ppm. This is how we can run the OCLT to prove/disprove the presence of organics in the water. You can buy just the FAS/DPD specific chlorine test for those time when you need specificity and continue having the guards using the DPD test to prove there is chlorine in the water during the day.

Through over a hundred thousand members here (tens of thousands of pools) we have found that not much credence should be given to pool store testing. While you would think that a "professional" would be the best, unfortunately in most cases it is quite the opposite. Between employees who blindly trust the word of chemical sales representatives and high school kids working in the pool store for the summer you end up with poor results from their testing.

 

[YippeeSkippy]

It's a Taylor dpd kit. I'll get the actual number... The guards test pH and free cl2, the local pool store tests to help us balance alkalinity, etc.

I'll save the trouble of beating around the bush. You *need* the proper test kit. I would suggest either the Taylor K-2006C (commercial level, no other numbered kit please) or the TF-100 (which is a better buy). TFTestkits.net or PoolSupplyWorld.com can both help you get it.

You should be testing pH, FC and CC often, and not bother with the pool store testing for CH, CYA or TA because nine times out of ten they're wrong. We have seen that too many times to count. Summer help, un-concerned help, need-to-make-a-sale help.... well, no one cares more for your pool than you. So you'd see to it it was done RIGHT. Amiright??

 

[Matrioux]

Through over a hundred thousand members here (tens of thousands of pools) we have found that NOT much credence should be given to pool store testing.

Fixed

 

[tim5055]

Fixed

Good catch. That's what happens when you cut/paste and don't re-read it

 

[Ed McCarron]

I was scratching my head on that one. ?. Looks like I need a new test kit and some education...

 

[Puppiesonacid]

Most of us do here that is why we are here

 

[jblizzle]

Welcome to TFP!!!

The cornerstones of the TFP method of maintenance are accurate testing using one of the recommended test kits and maintaining the correct FC level that is a function of your CYA level according to the FC/CYA Chart. This relationship is misunderstood or ignored by 95% of the pool industry even though it was proven in the 1970s.

We really need to know the requirements that you are held to.
For example, are you allowed to use CYA in the pool? (Being an outdoor pool, this would be very beneficial)
Are you limited in the FC level? (With a higher CYA, the FC must be maintained higher, but again, the "state" does not understand that so their recommendations may actually not allow you to maintain a safe/clear pool)>

 

[jeffbrig]

350,000 gallons? Hang on a second (counts on fingers AND toes). That's like 20x the size of my backyard pool. How the heck do you chlorinate something that size? Something tells me you aren't going to want to add upwards of 10 gallons of liquid chlorine each and every day, unless someone is delivering a chlorine truck to you regularly. Do you have a commercial chlorinating system? A bank of giant saltwater chlorine generators? Sorry, just trying to wrap my ahead around the scope of this...