Green Pool (Was black at first)

Hi,

Just opened my 30k gallon pool a week ago.

Some background info:

Pool has a sand filter and sand was replaced last year.
Pool is around heavy tree coverage and due to early snowfall last winter (MN) it was well covered with oak leafs which were removed in spring when the snow finally disappeared.
When cover was removed water was black. But I am sure it was the main reason for the black pool water as the year before it was clear with some debris on the bottom of the pool.


I used around 5 gallons of liquid bleach to shock and after a couple of days of filtering and back washing pool is now green (can hardly see bottom in shallow end) but it seems to be better than before.

My numbers for 5/29 were (Done with LaMotta Color Q):
FC 1.92
PH 7.1
TA 163
CH 190
CYA 9

Added that day 8.5 lbs of Soda Ash to increase PH.

My numbers for 5/30 are:

FC 2.46
PH 7.3
TA 209
CH 185
CYA 2

Now I think (here I could use advise), to add more Soda Ash, 5.5lbs to continue to increase PH.
And do another round of liquid bleach (could use advise here on quantity).

My phone app (Pool Pal) which I am using, also recommends to add 159 fl.oz or 9.5lbs of dry stabilizer.

I have been brushing on a daily basis. A small kleen cleaner robot is cleaning but the hoover bag seems to get lined with algea which contains the water in the bag when removed from pool.
It looks like the sand filter is working over time and I am not sure if it's performing right as the skimmer baskets show minimal action.
When pool is set to circulate by passing the filter the skimmers work fine. I am planning to pull the filter apart to make sure it not a clumpy mess.

Thanks,
Ernst

1. Algae is either dead, dying, or growing. Green algae is growing. Add 5 gallons of bleach EACH evening till the algae is ALL gone / brown. Brush the pool after each addition.

2. Meanwhile, read http://pool9.net/alk-step/ . Assuming that the ColorQ is accurate -- and I can't really assume that -- you need to lower your TA. Aerate to do so; your pH will rise. How much lower depends on whether you have a vinyl or concrete pool. Do not add any more soda ash.

3. Your CYA is too low, but it would be better to raise it AFTER the algae is dead. A good way to do so is use dichlor, which adds 9 ppm of CYA for every 10 ppm of chlorine added. See http://pool9.net/sams-dichlor50/

4. Do not add any other chemicals till the algae is dead, the pool is clean, and the TA is more reasonable.

5. We have plenty of evidence that electronic readers are generally very inaccurate and untrustworthy. However, I did some checking on the ColorQ Pro and would acknowledge it's better than most . . . but it's very sensitive to temperatures and wait periods (covered in the instructions). If you do not observe those requirements, you can get very inaccurate results. If you do follow the instructions, the chlorine test up to 5 ppm, the pH, test and the TA test are probably as accurate as the K2006. The calcium test has problems, and the stabilizer test is apparently erratic. The most comprehensive discussion I could find is here:
http://www.poolgeniusnetwork.com/for...photometer-are

6. You need to get a cheap OTO/phenol red kit, since you can't test chlorine accurately above 5 ppm with the ColorQ, and above 10 ppm, the sample may bleach out and read low or even zero.

Thanks Doc,

This am I did add unfortunately already additional Soda Ash (5.5lbs) to increase the PH.
My readings in the late afternoon are (I will verify my future ColorQ readings with my OTO test kit):

Pool has vinyl Liner:

My 5/31 (6 hours after soda ash addition)

FC 1.99
PH 7.6
TA 249
CH 189
CYA 3
Total Chlorine 5.27

Just Added this evening 5 Gallons of Liquid Chlorine, brushed and will repeat as instructed (and hope to see dead algae soon). Will do some reading on the other points.

Thanks for the advise.

Ernst

Quote:

---

Originally Posted by like2ct

FC 1.99
PH 7.6
TA 249
CH 189
CYA 3

---

The ColorQ is MUCH more accurate than an OTO kit; it's just not reliable at chlorine levels above 5 ppm. I'd still encourage you to get a K2006; they keep a long time, and even if you mostly use the ColorQ, there will be times when you need an accurate CYA or CH reading, or when the chlorine is above 10 ppm.

Pool still green, doing the daily 5 gallon liquid chlorine/brush job.

Just had 5" of rain and lot of tree crap in the pool.

Numbers for today (I have the K2006 kit on order).

6/2

FC 3.86
PH 7.4
TA 227
CH 186
CYA 9

Looking now for ways to prepare for aeration (considering making a PVC pipe aeration attachment for one or two of the return lines).

Have pump set to circulate and slide is running as I understand my PH is still too high to do a full blown aeration.

You don't have to do aeration fast -- it will take place slowly if you do nothing but maintain a lower pH. So, go ahead and lower the pH. If you can, adjust the pool returns to 'riffle' the water.

Worry about getting the chlorine up, and killing the algae. If it's still green with 5 gallon doses in the PM, go to 10 gallon doses! You'll spend less, killing it quickly than by slowly beating it to death.

Update, water seems to be a lighter green, brushing seems to produce smaller clouds of brown than before.

Numbers of 6/3 Just before adding 10 Gallons of Liquid Chlorine and brushing. Use slide and have returns pointed to surface to aerate. Also filtering again.

FC 3
PH 7.4
TA 177
CH 176
CYA 14

=====================

Numbers of today, just before another 10 Gallon liquid chlorine dump. Filter seems to be a lot cleaner. Still use slide and returns to aerate. The returns make the water ripple (no bubbles)

6/4

FC 1.33
PH 7.10
TA 188
CH 163
CYA 83

Don't have the K2006 kit yet. CYA number seems strange compared to previous measurements.

It's good that Fleet Farm has the chlorine on sale, :)

Thanks in advance for any advice/comments etc.

One of the observations I saw about the ColorQ was that the CYA measurements could be erratic.

You need to do another 30 ppm dose (10 gallons of bleach) added in the EVENING, and then do a chlorine test in the AM (before 9 am).

What COLOR is your water?

My CYA reading of the other day might have been a user error (you can put in the tube two ways and the wrong way is blocking the colorimeter "view")

Anyways. Pool water is a teal green. Only able to see the bottom at the shallow end.

My 6/5 8:30am numbers:

FC 1.33
PH 7.0
ALY 184
CH 172
CYA 8

I am sure that I am bleaching out. I tried the over 10PPM FC procedure but those numbers where very strange and I had lack of time for a redo. Have to make money to buy more Pool chemicals :)

K2006 kit should arrive tomorrow.

One observation my robotic pool cleaner is floating on the surface and doesn't want to "sink" to the bottom of the pool. The clean out of the cleaner showed some regular "waste and some worms" it wasn't clogged anymore with dead algae.

I've got something, created partly with you in mind:

http://pool9.net/pf-hist-form

with results here:

http://pool9.net/pf-hist-chart

+ Get a cheap OTO / phenol red kit. It won't bleach out, at any chlorine level, and will be useful even after you have the K2006 for quick checks.

+ Tell me what % bleach you are using.

Hi Doc,

Thanks again.

This AM when I posted my Color Q FC numbers I did do a FC measurement with my OTO kit and that one also looked like it was bleached out too (hardly any yellow). Now you state in your post that it should not bleach out.

Makes me wonder that my FC Color Q measurement might be accurate after all (or am I confused). Pool does have a Chlorine odor.

I am using the 12.5% bleach.

OTO is not super accurate, but it is super reliable. If it shows no chlorine, there's no chlorine.

Submitted my 6/6 numbers in the online spreadsheet. Still doing the evening 10 gallons of Chlorine and brush job. I am currently not filtering (only using vacuum robot) as I think the aerating will help at this moment. When brushing I have no more heavy clouds of dead algae.
It seems water color seems slightly better but still a teal green and bottom only visible on shallow end.

Sounds good.

I noticed on your pool report that the bleach was 12%. Fresh 12% bleach will add a full pound of chlorine (Cl2 gas equivalent) to your pool -- 10 gallons would be 40 ppm of chlorine. When I was cleaning up big commercial swamps, I'd usually dump the equivalent of 100 ppm into a pool all at once. I don't recall that doing so ever failed to 'turn' the pool within hours. You've added at least 160 ppm, though over several days.

I'm wondering if you have a bunch of ammonia in your pool. CYA is biodegraded by swamp slime (algae + bacteria). It can end up as harmless nitrogen, but it sometimes ends up as ammonia, and requires HUGE amounts of chlorine to clear. Do you remember what your CYA level was last fall?

Unfortunately I have no record or recollection of my CYA of last fall. One of the reasons I am now starting to record it all to eliminate guess work (second year pool owner).

I did submit my tonight's numbers (Yesterday did the usual 10 gallon Liquid Chlorine and brush job).

Finally FC seems to hold at a higher number, Used K2006 kit to measure 12 ppm as ColorQ as expected reported hi for reading (limit 10 ppm unless using workaround). Also used K2006 for ALY measurement which was similar to ColorQ.

CYA measurement done with ColorQ as K2006 didn't yield any noticeable measurement which might be user error as was first try. After mixing 7ml of pool water and 7ml of the agent and mixing for 30 seconds the mix was clear and not obstructing view to the black dot in the tube.

Can now see vacuum at bottom of pool and it looks like the chlorine is starting to do something. Not sure why it now starts to do it's job. We had rain and thunderstorms last night and during the day and this added 2" water to pool. I am aerating non stop and not filtering.

Didn't have a lot of time tonight. Added 2 gallons of liquid chlorine and did a very quick brush job. I did read about the CYA potentially being biodegraded. Not sure if tonight's measurements are an indication or of any help.

Thanks again.

Quote:

---

Originally Posted by like2ct

CYA measurement done with ColorQ as K2006 didn't yield any noticeable measurement which might be user error as was first try. After mixing 7ml of pool water and 7ml of the agent and mixing for 30 seconds the mix was clear and not obstructing view to the black dot in the tube.

---

Actually, the K2006 gave you a definitive measurement: ZERO. You have NO CYA.

If you have access to a Sams Club, you need to get dichlor from them, and chlorinate with that: for every 10 ppm of chlorine added with dichlor, you get 9 ppm of stabilizer. http://pool9.net/sams-dichlor24/

Otherwise, you can check Lowes, Home Depot, or Ace Hardware for dichlor showing 56% available chlorine (NOT: 56% dichlor!). Most of the dichlor sold today is diluted.

Until you have some CYA in your pool, the only meaningful measurement of chlorine loss is from late evening to early morning: daytime loss under full sun would be expected to complete, regardless of chlorine level.

Updated my numbers for today.

Have 50lbs of the Dichlor with the 56% available chlorine. Not entirely sure how much to add though. Do I build it up slowly?

Used some pool calculators and it looks like 9oz yields around 1 PPM of FC and 0.9 CYA. Looks my goal is 40 CYA.

Will start with 72oz as it's easier to add as I think that I need a lot more. Current FC is 8.28.

Yes, slowly.

Basically, simply use it to chlorinate, till your CYA is at your target level.

You'll find that initially (while CYA is low) you'll lose chlorine quickly. But as the CYA increases, chlorine levels will be more persistent.

Added today's numbers. Didn't measure CYA as I understand below 30 no way to measure with my tools, my best guess based on FC level is around 9 as my FC went from 8 to 18 ppm (Had overcast and no sun).

Will add another 72oz of dichlor. Water still light green. Can see bottom. Not filtering just circulating and aerating.

Until your CYA is higher, add your large doses late in the day, so they can work all night before being hit by sun.

Posted my numbers for today. Did a FC measurement this am and a complete one this pm. Still a light green color. Started to filter around noon.

Just Added 72oz of Dichlor. Hopefully another session will give me an ALY I can actually measure. My best guess is that I should be around 25 right now.

I'm sorry, pools are running together for me. Please fill out this pool equipment chart:

http://pool9.net/pf-pool-form/

What's an "ALY"?

Hi Doc,

I meant to write CYA not sure how I came up with the ALY (Probably the Chlorine affecting my brain).

I am in your pool chart list as like2ct.

Pool is starting to clear up still a little bit of green at the deep end.

Not this form which you've already done:

http://pool9.net/pf-hist-form/

But this form, which you haven't:

http://pool9.net/pf-pool-form/

Looked at your pool form. You have an S200 filter which has 'rated' flow of 44 GPM, but an optimal flow of 33 GPM (2.2 sft x 15 GPM/sft):

https://www.hayward-pool.com/images/...s_perfdata.gif

with a 2 HP Pentair Super-flo, which is functionally a 70 - 90 GPM pump in your situation!

https://lh4.googleusercontent.com/-N...0/SuperFlo.jpg

Unfortunately, that is a massively imbalanced pairing. The pump is way, way too big for the filter. As a result:

+ You are probably missing sand, that has been 'blown out' during backwashing.
+ You are probably pushing algae THROUGH the filter, rather than capturing it.
+ You are wasting at least 1/2 of your pool electric bill -- making your filtration worse in the process.


Here's what you need to do, immediately:

1. Install a ball valve between your pump and filter. Throttle the flow, till your *clean* filter pressure is 18 psi or lower.

Hayward 2" ball valve

2. Once the ball valve is in place, open the filter top, and check your sand level. You'll need this dome wrench, if you don't already have it:

Hayward S200 dome wrench

3. If the sand is low, add labeled filter sand to the correct level.

Longer term, you'll need to downsize your impeller / diffuser to 3/4 HP. Your 2HP motor will be a bit less efficient running the 3/4HP impeller, but it will run VERY cool, and last forever AND you'll probably still cut your bill in half.

3/4 HP impeller (1/2 & 3/4 HP impellers are the same)
3/4 HP diffuser
Seal kit

Amazon is not selling the seal kit directly, so here's another source:

Seal kit

Just out of curiosity, how did you end up with such a big pump coupled to that filter?

I should have picked up on the over sized pump problems, from the high filter pressures you reported, but I've just started working with those forms, and haven't gotten used to all that I can learn from them.

Hi Doc,

I appreciate it a lot for you to take the time to review my pool equipment.

The pool came with the house we purchased a year ago. I would have never given it any thought that there's a potential pump/motor mismatch. Motor seems to run very hot (when water hits it vaporizes).

Here some pictures of the pump label, motor label (I am pretty sure it says 2.0 HP) and general setup.

Pump, https://dl.dropboxusercontent.com/u/...613_172827.jpg

Motor, https://dl.dropboxusercontent.com/u/...613_173007.jpg

General plumbing:

https://dl.dropboxusercontent.com/u/...613_173138.jpg
https://dl.dropboxusercontent.com/u/...613_181256.jpg
https://dl.dropboxusercontent.com/u/...613_181314.jpg

Looks like your Amazon links are a bit mixed up.

The 3/4 HP Impeller shows the seal kit.
The 3/4 HP diffuser shows a 1/2 HP Impeller
The Seal kit shows the diffuser.

I almost think it's easier to install the long term fix as installing the ball valve seems to be a big challenge with the current routing of the pipes. Enabling the slide reduces the pressure by 5 points.

Thanks,
Ernst

Tonight's measurements:

FC 38 (K2006)
TA not able to measure with K2006 (goes from green to blue then yellow), ColorQ shows 88 which I suspect is too low, HTH Test strip shows 120-180 range which is more in line with previous measurements.
PH 7.3 (ColorQ)
CYA 100 with K2006 (did it twice), 49 with ColorQ and 30-50 with HTH guess strip. I hope that my ColorQ and HTH strip are accurate ;)

Based on my best guess CYA based on the Dichlor additions, I expected to be in the low thirties.

Will update spreadsheet with tonight's confusing numbers.

Did review my spreadsheet. I did a total of 5 rounds of 72oz Dichlor to raise the CYA which measured zero with K2006 when I started with the Dichlor. The ColorQ showed very low CYA numbers and the high one was an user error (test tube rotated 90 degrees). When measuring the CYA with ColorQ the test tube actually became smooth "blurry" as in previous measurements the crushed tablet didn't really dissolve. The one time I did measure the FC in the evening and in the morning the Dichlor added 9PPM of FC. So my best guesstimate CYA would have been in the low forties (In my previous post I thought that I only added 4 rounds of 72oz of Dichlor).

Thanks, for reading.
Ernst

I fixed the links above, but I'm going to need to do a new set. After looking at your plumbing, and hearing your description of the pump motor temp, I'm think you need a more complete rebuild.

If you replace your piping, and replace your motor with a 1HP 2 speed, you'll filter better, and save a LOT of money. Your existing motor is likely approaching failure, as hot as it's been running.

Pentair 355003S 1 HP 2 spd Square Flange Motor for SuperFlo Pump
Pentair 355067 1 HP impeller
Pentair 355617 1 HP diffuser

When you buy, do so by part # (355003S, 355067, 355617) -- the parts are confusing, and overlap different models in odd ways. You can should confirm using the Pentair Superflo manual, pg 12, before buying.

The seal kit is the same as above.

When you re-install, use MIP / FIP combined couplings, with blue dope:

2" MIP
2" FIP
Blue dope

Use those pairs every where you cut pipe, so NEXT time, you can repair by simply unscrewing 1/2 of the pair! If you prefer, you can use unions, instead:

2" PVC Union

Cool,

I ordered the items specified. Looks like the process is pretty straight forward (watched some video's). Should be able to do it next Saturday.

Pool is clear. Weather is too bad to do some measurements.

Thanks again,
Ernst

Please let me know how it goes.

Thanks!

Installed today the following items:

Pentair 355003S 1 HP 2 spd Square Flange Motor for SuperFlo Pump
Pentair 355067 1 HP impeller
Pentair 355617 1 HP diffuser
Replaced seal plate seal, "rotating" seal, seal plat o-ring, quad ring. The seal set came with clear instructions so that helped.

As expected it was pretty straightforward. The not so clear part is the wiring for the two speed motor as the diagram on the side of the motor was not readable.

One of the hot wires goes to connection numbered with 1 and the second hot wire is wired directly to the black wire of the speed switch (240V connection). I just used a wire nut to make the connection to the switch.

The ground wire goes under the green nut. I did bench test it (up side down bucket) and it ran in both speeds before mounting it in the pump housing.

Here some pictures of the install:

Wiring of motor

Seal plate with new seal

Rotating portion of seal

Impeller

Diffuser

Pump housing

Finished result

Running now 22psi

Motor is warm to the touch, so no longer boiling hot as the old one (I measured 225F on the old one).

Priming the system went smooth. Looks like pump has difficulty running at low speed and doesn't look like it will prime itself at that speed. I am not planning to use the low speed.

Home Depot had a 240V mechanical timer on sale ($15.00) so I picked one up and plan to install that later on this week.

Pressure went down to 22psi (Old motor 2HP with matching impeller/diffuser ran 30psi).

Still have to check the sand filter sand level. Pool water is currently crystal clear but FC is still high (>10ppm).

Turned on the heater as the kids are starting to get impatient.

Thanks for all the advice. Will do tomorrow some accurate measurement to see where I am at.

Ernst

Thanks so much for the follow-up.

I'm looking forward to seeing the end results!

Normally, you don't prime on low -- in fact I don't believe any of the pumps are capable of priming on low. In most applications where I've run 2 speed pumps, the pump runs on low 24/7, unless vacuuming, backwashing, or under heavy load.

If you want to be able to toggle the pump on and off, you have to start the pump on high, and then switch to low. Intermatic has some ganged timers that allow that. Another method is to install a high quality check valve within a few feet of the pump on the suction side, to prevent prime loss.

Something to keep in mind is that sand filter performance actually increases as flow rates decrease, so running the pump on low 24 hours uses less electricity than high for 8 hours AND filters better. Depending on your weather and debris loading (here, the June forecast is hot & humid with afternoon thundershowers dumping leaves and debris into your pool!), you may need high speed, say from 6 - 9 pm, to drag surface goop and leaves into the skimmer.

You talked me out of the timer and some work thanks ;)

Just posted my numbers. Water is crystal clear and my numbers are getting better and better. I am still "recovering" from the Dichlor CYA increase exercise so no chemicals added. Pump is running 24/7 on low speed.

Today first day that the kids used the pool (no green hair or bleached swimwear).

FC 9.73 with ColorQ (measured this morning around 9:00am FC of 11 with K2006).
PH 7.5
ALY 141 with ColorQ and 130 with K2006
CH 185
CYA 51

Will do an early morning measurement to check my FC.

Thanks Ernst.

Great!