Algae in condominium Homeowner's Association pool

Postby **Denali** » Mon 08 Jun, 2009 02:18

Henry_R wrote:pH is in the 7.2 range as of about 10pm, and still in that range at 12:45am. The chlorine is still measuring near 0.5 to 1. The vial is not completely clear when I test it so it must be just low not zero.

Nothing I can do without another dose and I'm out of it. Shy of throwing 1lb of dichlor in there which is not enough for a 22000 gallon pool I have no more chlorine and won't be able to add more until about 6pm due to my schedule today.

A week is a long time for CYA to register.
Does it begin to have effect on chlorine retention sooner than it shows in the test?

From my experience the CYA will register in a day or two. The week I mentioned is probably overstatement but better to wait and see than to add more and get the level too high.

The chlorine tabs will give you some chlorine and some CYA but also lower pH. You can use them and keep an eye on the pH.

From the look of the pool it is moving along even faster than I thought it would which is great.

Postby **Henry_R** » Mon 08 Jun, 2009 08:25

This morning I tested the TA and CH as well as pH and chlorine again.
pH seems to be moving downwards. TA read close to 30. CH is around 300ppm.
Chlorine is nearly unreadable. There is some color but it's very white.

pH reads in the 6.8 range this time. Lower than last night so I'm going to not do anything to reduce it further is possible. That dry acid should only have reduced it to 7.4 or so. I hope it doesn't go too much lower than 6.8.

The TA test seems to read only 30. So I guess that goes with the pH creeping down. What do I do to increase it some?

I also checked CYA and it seems to be a little higher. If I'm understand the test right the dot is supposed to be clouded over by the water and begin to seemingly dissappear?
This begins now around 50ppm vs getting to the top. SO CYA is moving upwards. Hopefully not too high.
I'm still not certain I'm doing it right though.

The water is also still VERY foamy this morning, but I don't think it looks green; it's not blue yet either though. With some luck my work won't be undone during the day if the chlorine stays (even being at 1 is better than zero right?) put with CYA above 30 at least. The 4lbs of CYA was only supposed to add 10ppm for 2lbs so 20ppm total. With luck it won't overshoot 50-70 and it a few more days I'll get a decent reading.

When I get more chlorine tonight I'll add enough to bring it to shock level and maybe that CYA will let it stay put this time.

BTW, the test kit I'm using is Leslie Pool supply DPD test. I'm not sure how accurate it is. It cost enough: almost $40. It has enough vials for probably a few hundred tests though.

Postby **mr_clean** » Mon 08 Jun, 2009 09:48

I think your pool is looking alot better, good job........ :thumbup:

as for conditioner, if it was a "granular" form and you added it threw the skimmer it will take a week or two to fully disolve so backwashing sand filter would release it, so do not. :wtf:

if powder form conditioner (baby-powder) and you added to skimmer will mix within a couple hours.

keep it up and the next thing you know your going to jump in & enjoy your work.

Postby **Denali** » Mon 08 Jun, 2009 18:06

Henry_R wrote:This morning I tested the TA and CH as well as pH and chlorine again.
pH seems to be moving downwards. TA read close to 30. CH is around 300ppm.
Chlorine is nearly unreadable. There is some color but it's very white.

pH reads in the 6.8 range this time. Lower than last night so I'm going to not do anything to reduce it further is possible. That dry acid should only have reduced it to 7.4 or so. I hope it doesn't go too much lower than 6.8.

The TA test seems to read only 30. So I guess that goes with the pH creeping down. What do I do to increase it some?
I would use some baking soda to raise the TA. The pH will go up a bit which you want also. You want the pH up to at least 7.2. If you haven't found this yet, check http://www.poolcalculator.com/ to figure doses.

I also checked CYA and it seems to be a little higher. If I'm understand the test right the dot is supposed to be clouded over by the water and begin to seemingly dissappear?
This begins now around 50ppm vs getting to the top. SO CYA is moving upwards. Hopefully not too high.
I'm still not certain I'm doing it right though.

The water is also still VERY foamy this morning, but I don't think it looks green; it's not blue yet either though. With some luck my work won't be undone during the day if the chlorine stays (even being at 1 is better than zero right?) put with CYA above 30 at least. The 4lbs of CYA was only supposed to add 10ppm for 2lbs so 20ppm total. With luck it won't overshoot 50-70 and it a few more days I'll get a decent reading.

When I get more chlorine tonight I'll add enough to bring it to shock level and maybe that CYA will let it stay put this time.

Not sure what is causing the foaming but addition of chlorine should take care of it. Chlorine will be used up even with proper CYA level when you are fighting algae. When the algae is all dead is when the chlorine levels will stabilize and you can back off the shock levels.
BTW, the test kit I'm using is Leslie Pool supply DPD test. I'm not sure how accurate it is. It cost enough: almost $40. It has enough vials for probably a few hundred tests though.

Postby **Denali** » Mon 08 Jun, 2009 18:09

On CYA levels and testing. The test can be hard to read. I would leave the CYA level where it is for now. Test again in a few days and next time you get to a pool store, have it tested and compare with your own testing. Should give you an idea if you're reading the test right.

Postby **Henry_R** » Mon 08 Jun, 2009 20:40

My neighbor and I wet to get more of the 10% chlorine shock tonight. She's concerned it's getting to be too expensive to use liquid and I'm about to agree; cost was $3.50 per gallon at Lowes.

Can/should I switch to trichlor tabs through the chlorine/bromine feeder tomorrow if I put in the 10% chlorine shock tonight? I have three 3" tablets. I don't want any bad reactions. I also can get dichlor too. That I cannot dispense through the feeder as it states use only trichlor. I'm a bit uncertain what to use given the still somewhat uncertain chemistry balance. How fast will the tabs disolve?
They are 8 oz each. Won't they increase pH some too? My neighbor is right $3.50 per gallon and three at a time to get to shock level according to the poolcalculator is too expensive to continue to use as shock.
Once we get to maintenance level perhaps we can go that route.

I also got a pool brush and I think I'm going to do some before I add more of the liquid shock tonight.

Postby **chem geek** » Mon 08 Jun, 2009 21:17

A true cost comparison of different sources of chlorine is here where chlorinating liquid and bleach are actually less expensive than Trichlor and especially Dichlor when you account for the pH balancing product you need (i.e. pH Up or Arm & Hammer Super Washing Soda). Only Cal-Hypo is comparable in price or sometimes less expensive, but it will raise Calcium Hardness (CH). Remember the following chemical rules with these other sources of chlorine:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by 7 ppm.

With the chlorinating liquid, the pH rises when you add the chlorine, but it will drop back down as the chlorine gets used up. The Trichlor tabs/pucks dissolve too slowly to be used as shock (usually 5 days to dissolve, though with water flow in a skimmer with the pump on 24/7 it can take a couple of days), though you can sometimes get Trichlor in powder form BUT it increases CYA. Dichlor is in powder form and dissolves quickly, but increases CYA. Cal-Hypo should be pre-dissolved in a bucket of water, but it increases CH.

Richard

Postby **Denali** » Mon 08 Jun, 2009 22:19

chemgeek gives you good info in the post above mine. It will cost you to keep the pool at shock level. I find liquid chlorine to work best and cheapest.

The tabs will LOWER pH, not raise it. Keep that in mind as your pH is already low.

Once the pool is clear the cost to chlorinate drops drastically especially as the pool isn't going to be used.

I know this is tough as it comes out of your pocket and it isn't your pool. One way to look at this is that you're now paying for all the chemicals you didn't put in while it was turning green.

Postby **Henry_R** » Mon 08 Jun, 2009 23:26

Thank you again.

I'm not terribly concerned with the costs to me. The HOA board cut me a check immediately for the supplies I purchased this weekend. The property manager had business with the president here and left the check for me with her. I deposited it right away. Of couse I spent $32 more on the chlorine and a brush again this time. I brushed the pool till I was sore. The pole I'm using didn't help it's a recycle from another neighbor and it keeps retracting. When I push it it wasn't brushing as hard as Id've liked.
This is the first time I've done this too. Didn't have the brush until now. Hopefully, the 2.5 gallons of 10% chlorine will work again as the 6% began to on Sunday morning. There is still a lot of foam on the surface. It's almost seemed to increase with the addition of the chlorine.

How soon can I get a usable reading of the FC level? First light in the morning?

The costs to shock the pool are increasing though that is the concern to the HOA president.
I've dumped 1.38 gallons 6% bleach on Sat night, 1.38 gallons on sunday morning, 2 gallon of 10%
last night and now 2.5 gallons tonight. Approx. total cost over $28, not to mention gasoline to get to/from Lowes. I don't drive and my neighbor has a pickup so gasoline costs are expensive for her.

I'm not sure if this is a good price or not.

I think I'm going to go shopping online for the 10% chlorine.
I think Lowes' price might not be the best I can do in the end.

Postby **Henry_R** » Tue 09 Jun, 2009 11:44

Once again the chlorine is near zero. I dumped what should have been enough to bring it up to 10ppm last night; two and a half gallons according to the poolcalculator. Either that 10% liquid shock was old
and ineffective or something else is wrong with the water chemistry. There are date codes on the liquid shock bottles. How do I read the codes? The bottles were dirty. Perhaps they were old stock. Is it not true that chlorine degrades in the bottle over time?

How long after adding liquid chlorine should I be able to get a good reading?

The test kit is a DPD type not OTO and I'm wondering if that the problem.
The OTO kit I returned since it was missing it's CYA testing tube(dot tube), but it showed
chlorine at least at 5 or more. The DPD test show no color at all. Even last night after I added all that chlorine there was no reading. Shoudn't there have been some reading?

The pH seems to have stabilized at 7.5 and it's staying put for now.

The water is still murky and still has a seafoam greenish look, at least to my eyes.

The filter pressure has bugged up to 15psi from 12.5psi it was staying at before.
I'm not entirely sure that gauge is accurate either due to it's age.

Postby **Denali** » Tue 09 Jun, 2009 21:14

Henry_R wrote::problem:
Once again the chlorine is near zero. I dumped what should have been enough to bring it up to 10ppm last night; two and a half gallons according to the poolcalculator. Either that 10% liquid shock was old
and ineffective or something else is wrong with the water chemistry. There are date codes on the liquid shock bottles. How do I read the codes? The bottles were dirty. Perhaps they were old stock. Is it not true that chlorine degrades in the bottle over time?

How long after adding liquid chlorine should I be able to get a good reading?

The test kit is a DPD type not OTO and I'm wondering if that the problem.
The OTO kit I returned since it was missing it's CYA testing tube(dot tube), but it showed
chlorine at least at 5 or more. The DPD test show no color at all. Even last night after I added all that chlorine there was no reading. Shoudn't there have been some reading?

The pH seems to have stabilized at 7.5 and it's staying put for now.

The water is still murky and still has a seafoam greenish look, at least to my eyes.

The filter pressure has bugged up to 15psi from 12.5psi it was staying at before.
I'm not entirely sure that gauge is accurate either due to it's age.

It's quite possible that the chlorine level is quite high and it's bleaching your test so showing clear. Chlorine does lose strength over time so it may have been weaker than expected.

The filter pressure going up is what you would expect as it cleans the water.

I forget if you have vacuum gear. Have you been able to vacuum the pool? Much debris in there?

Postby **Henry_R** » Tue 09 Jun, 2009 22:27

If I were to take a sample to a pool store would their equipment be better at determining the amount of chlorine? I realise it's only as good as the person doing the test but I might take the sample to a smaller shop that's been around for a long time. They might have better personnel doing the test and their webpage claims they use the latest testing equipment.

What of the color still looking greenish? It had started to clear before I went to the 10% chlorine vs the 6% regular bleach. Shouldn't the water be clearer if there is a really high amount of chlorine?
Should I not add any chlorine tonight and check the level in the morning maybe?

I know the pressure will increase, but what concerns me is whether it will increase too high before the water is stabilized and well chlorinated and I have to backwash out the chemicals I've added.
I don't fully trust the gauge, as I said since it's from 1991 like the filter. If it were up to me I'll be looking
for a new gauge at some point.

No, no vacuum gear due to storage concerns. WE used to have a pool building, but had
to be torn down. The only place I can store the hose would be inside the area around the pump.
Not a good idea but it might have to do. The pole for the skimmer I've had to store in my patio.
I don't really have room for the hose though.

The brush I bought has a port for the vacuum hose so I'll look into getting the right hose and skimmer attachment. How long a hose should I be looking at for a minimum? What do I do about my not being able to see the bottom? I won't be able to tell if I vacuuming anything other than water without being
able to see.

Is the lack of the main drain being open hindering my effort do you think? There is no valve to redirect flow. We were told by one of the companies that the pipe was clogged. If the drain were working would it be likely that the pool would be cleaner by now?

Postby **chem geek** » Tue 09 Jun, 2009 23:55

Henry_R wrote:What of the color still looking greenish? It had started to clear before I went to the 10% chlorine vs the 6% regular bleach. Shouldn't the water be clearer if there is a really high amount of chlorine?
Should I not add any chlorine tonight and check the level in the morning maybe?
:
:
Is the lack of the main drain being open hindering my effort do you think? There is no valve to redirect flow. We were told by one of the companies that the pipe was clogged. If the drain were working would it be likely that the pool would be cleaner by now?

If there is green yet the chlorine level is high, then the green is likely to be from copper. If the green tends to go away as the pH drops when the chlorine levels return to normal (or if you intentionally lower the pH), then this would confirm that it is copper. A metal sequestrant could be added if that is the case. On the other hand, you reported in an earlier post that you avoided anything that had copper in it, so perhaps the green is still algae -- if it's near the bottom of the pool where the chlorine perhaps isn't getting well circulated, then that could be the case.

The lack of a main drain will significantly slow down clearing of a pool if the circulation near the bottom is poor. Pointing the returns diagonally downwards can help improve water flow and brushing can also help. However, this will clear up cloudiness, not a clear green tint.

Richard

Postby **Denali** » Wed 10 Jun, 2009 00:03

Henry_R wrote:If I were to take a sample to a pool store would their equipment be better at determining the amount of chlorine? I realise it's only as good as the person doing the test but I might take the sample to a smaller shop that's been around for a long time. They might have better personnel doing the test and their webpage claims they use the latest testing equipment.
Probably a good idea to get a full testing done. From the pics you posted before I would have expected the pool to continue to clear. The greenish color could indicate copper in the water. If they are able to test for copper that would be helpful.

What of the color still looking greenish? It had started to clear before I went to the 10% chlorine vs the 6% regular bleach. Shouldn't the water be clearer if there is a really high amount of chlorine?
Should I not add any chlorine tonight and check the level in the morning maybe?

I know the pressure will increase, but what concerns me is whether it will increase too high before the water is stabilized and well chlorinated and I have to backwash out the chemicals I've added.
I don't fully trust the gauge, as I said since it's from 1991 like the filter. If it were up to me I'll be looking
for a new gauge at some point.
Backwashing away the chemicals really isn't a concern. You don't lose that much water while backwashing.

No, no vacuum gear due to storage concerns. WE used to have a pool building, but had
to be torn down. The only place I can store the hose would be inside the area around the pump.
Not a good idea but it might have to do. The pole for the skimmer I've had to store in my patio.
I don't really have room for the hose though.

The brush I bought has a port for the vacuum hose so I'll look into getting the right hose and skimmer attachment. How long a hose should I be looking at for a minimum? What do I do about my not being able to see the bottom? I won't be able to tell if I vacuuming anything other than water without being
able to see.
Agreed, I wouldn't vacuum until you can clearly see what's at the bottom. Hose length would be the distance from the skimmer to the furthest point in the pool. Add maybe 5 ft to that length.

Is the lack of the main drain being open hindering my effort do you think? There is no valve to redirect flow. We were told by one of the companies that the pipe was clogged. If the drain were working would it be likely that the pool would be cleaner by now?

Main drain can be helpful but it isn't critical at this point. The foaming and green tinge is a good reason to get the water retested and see if something is out of whack. Seems to have started when the CYA got added and that shouldn't have caused anything to happen.

Postby **Henry_R** » Wed 10 Jun, 2009 00:11

Thank you for your reply.

I have no idea where copper would be introduced since I have added nothing, but the pH reducer(dry acid), CYA, and two different strengths of sodium hypochlorite(6% and 10%).

Unless one of the "inert ingredients" in either the bleach or the liquid shock had copper I don't know how it could be in there. The bleach was regular unscented generic walmart bleach that is 6% sodium hypochlorite. The liquid shock is 10% sodium hypochlorite. Both list the remaining ingredients as "inert".

It might be algae, but if it is I'm suprised since I did brush the walls and floor to expose any lingering algae to the chlorine. Not to mention the amount of chlorine I've added.

I am going to take a water sample to a pool store and have it checked. I'm not certain I trust my tests at this point.