Algae ?

[mrdwkds]

Hi fellow Poolers, newbie here.
New to the site and unfamiliar where to post this question but here goes.
Just opened the pool today and to my surprize I have a brown hard film caked on the side of my vinly liner above the water line.
Closed the pool last season clean, and full of cholrine as usual.
Question: will a side wall cleaner and some scubbing remove this?? My daugther WILL not go in with that. SO Gross. She's 16, and it is gross.

Here's the other other problem I have.
After opening and getting the filter running my pool guy suggests to pour 4-5 gallons of cholrine in and run the filter for 24 hrs before a sample is tested. (I have a 11,000 gal above ground pool with a sand filter).
After this was running for about 2 hrs I noticed on the bottom of pool below the discharge nozzle, brown multi-colored sand? or algae enough to cover the palm of your hand. As the filter ran for a couple of more hours more of this stuff was settling all around thru out the pool.
Okay, thought it was sand from the filter but my sand is white.So anyone ,is this algae that grows within 2 hours? and what do I do. I've had the pool for 3-4 years and changed the sand 2 times. So any help??
Thanks Mrdwkds.
ps sorry if I went long

[Watermom]

Can you give us a current set of water testing results taken with a drops-based kit (not teststrips).

Do NOT pour that much chlorine in the pool at once. (What kind of chlorine are you using? Bleach? Liquid chlorine?) That would take your chlorine up to between 22-27ppm which is WAY too high.

Repost with numbers and someone here can take a look and try and help. Also, what is the pressure on your filter and have you backwashed any?

Welcome to the forum!

[mrdwkds]

Thanks for the response Water Mom.Don't have any numbers as of yet but will do in the next day or so.
As far as the chlorine, yes Liquid. I think it's Sunset brand? and yes, I backwash the system when filter pressure is 15-18 psi, or when I see the water flow from the discharge hose slowing down. Maybe once every week or so.

[Watermom]

Ok. We'll wait for some numbers. Regarding backwashing -- the general rule is to backwash whenever the filter pressure rises 8-10psi over your clean filter pressure. Post when you get the numbers and somebody here can take a look for you.

[mrdwkds]

Okay here's the #'s I read from the dye tester I bought after vacuming the pool.
PH between 7.2 -7.6
BR/CL 6.5/3.0. (this was brite yellow)

So not knowing what to add I had a sample tested at the store and here's their #'s.
Temp 75
Saturation Idx 0.3
TDS not tested
CYA 10
Tot. Chlorine 4.6
Free chl. 4.6
PH 7.9
Total Alkalinty 110
Adj. Akal. 107
Total hardness 200
So after all that I bought a PH reducer and added 1.25 lbs
Then added 2.5 lbs of 100 Stabilizer and broadcast 1.25 lbs and socked 1.25 lbs
Filter pressure reads 14lbs.
will run filter for 24hrs and recheck the numbers
but still after 30 mins of filter runtime I have these brown deposits already
so there ya go guys and gals any help ??
Thanks Mrdwkds.

[aylad]

In your first post you said that you had the brownish deposits above the waterline. In areas where it's "caked", can you scrape it off without damaging your liner? If so, I would do that and then try a sponge with a paste of baking soda and water to try to remove any residual. As for the stuff that you saw settling around the bottom of the pool, my bet would be sand that is either blowing into the pool due to a broken or cracked lateral in your sand filter, or dust/pollen that is in your water. I can't think of any kind of algae that would multiply so quickly that you can visually see it increase in a 2 hours period. I would vacuum the brown stuff out to waste, but watch your returns when you turn the pump back on to filter and see if you notice any sand blowing into the pool. If it is algae, then shocking the water will take care of it. However, I don't think that's the problem because if you have enough algae to be that visible all over the pool, 1)you should have some combined chlorine, which you don't, according to your posted numbers, and 2) it should be green, not brown. My bet is on sand.

The brown deposits that you refer to in your last post--are those the sandy looking deposits settling on the bottom, or are those caked deposits elsewhere in the pool? Are they loose where you can disturb them by rubbing with your hand and causing the brown to dispurse, or do they appear to be more like stains?
Is there a source near you for excessive dust/dirt--wells being drilled, new construction, etc? I haven't looked at your profile yet to see what part of the country you're from. Is there a great deal of pollen, maybe?

Make sure that you recheck your pH today--don't know what effect 1.25 pounds of reducer will do to it, but you want it to stay above 7.0, and preferably in the 7.2-7.6 range. If it goes too low, you can use Borax to raise it.

As for the stabilizer, make sure that the amount that you broadcast is swept around regularly and not allowed to sit on your liner--it is acidic and will stain at the least, or possibly damage the liner at the very worst. I personally would backwash the filter, then vacuum the broadcast CYA into the filter and let it disperse from there. 2.5 lbs seems like a lot for an 11K gallon pool, though--you might want to consider just vacuuming it to waste along with the brown stuff and then rechecking a CYA level after the amount in the sock has had time to dissolve (allow 3-4 days after it's dissolved to retest because it often takes several days to show up in your water and it's much easier to add more later if it's low than it is to reduce it if you overshoot. You want to start with about 20 ppm in your pool.)

Finally, what is the source of your fill water? Is it possible that there are metals in the water (iron, copper)? Aside from the brown deposits, what does your water look like? Clear? Cloudy?

Sorry for all the questions, but sometimes it takes some narrowing down in order to zero in on a solution!

Janet