New Member Needs Help With Algae

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Hi All,

I've been reading over this site and decided to join. Hopefully I'm on the right track with my signature and other info. So we've been in this house for about two years and I've never had any issues with algae. Starting about 3 weeks ago, algae started appearing every 4-5 days and has become worse since. At this point, algae now appears every morning when I go check the pool. The water is very clear but I can see the green algae spots on the floor and walls. I've been brushing and vacuuming to waste but nothing seems to be stopping it.

As far as chemicals go, I currently use 3" tablets, Chlor-Brite and Soda Ash. The tablets are nice to use due to frequently being gone, but after reading this site I'm going to attempt to switch to liquid chlorine. The tablets are put into a floater. When algae is present I shock the pool with Chlor-Brite. I balance the PH using the Soda Ash. I've also tried algaecide from Leslies with no luck. Now for the important stuff. Here's my test results:

Last night at 11:00 PM:

FC: 5
TC: 5
CC: 0
PH: 7.2
TA: 120

This morning at 10:00 AM (Algae visible again):

FC: 5
TC: 5
CC: 0
PH: 7.2
TA: 120

Unfortunately this is all my Leslie's test kit shows. After reading some pages on this site I've gone ahead and ordered a TF-100 and it should be in soon. I've taken the ladders and steps out of the pool and now have the pump running 100% for 24 hours to see if the algae returns in the morning. Can you all think of anything else I can try to prevent algae from appearing? Thanks in advance for your help. Now I'm off to search for liquid chlorine again since I didn't find any earlier today. :brickwall:

Darren
 

tim5055

Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
10,425
Franklin, NC
Well, until you get the TF-100 we are kind of at a stand still because we don't know what your CYA level is. The pool industry refuses to recognize the connection between CYA/Stabilizer and the ability of chlorine to do it's thing sanitizing the water. others here can give you the scientific details if you want, but lets just say CYA locks the ability of chlorine to sanitize. The more CYA you have the more chlorine you need to keep in the pool to keep algae at bay. I took over my pool with a CYA of about 250 (CYA tests above 100 are just a guess, not very specific contrary to what the pool store says). With a CYA of 250 I had to keep my chlorine level at around 20 just to keep algae away. Those "easy" 3" pucks are almost half CYA so your level has been rising as long as you have been using them.

The "Chlor-Brite" seems to be standard 10% chlorinating liquid with a fancy label and ha high price. Most of us around here just use generic liquid bleach from WalMart. A 121oz bottle at 8.25% runs about $2.57 in my area.

Your pH is being pushed down because of the puck usage also. Trichlor pucks are extremely acidic so that is why you are constantly needing to add soda ash. Plus, if you need to raise pH, borax is usually the best choice. Borax raises the PH and also raises the TA level just a little. The soda ash raises both the pH & TA. Your TA is a littl eon the high side as most of us find the pH more stable with the TA under 100.

How much Pool School have you read? Start with these:
ABCs of Water Chemistry
Recommended Pool Chemicals
How to Chlorinate Your Pool

So, welcome to TFP!!
 

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Thanks guys. I'm reading through the links and getting familiar with all the processes. I'll pick up some bleach at Walmart tomorrow (it's $2.57 here in NC too) and hopefully my TF-100 will be in by the end of the week. Based on the phone number on the TFTestkits.net page, I'm hoping the shipping is pretty quick since it's in NC (though I don't know where it ships from). I'll update my test results once the kit arrives.
 

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Just got my TF-100 and here's my results:

FC: 18
TC: 19
CC: 1
PH: 7.2
TA: 170
CYA: 100

I did the CYA and TA test twice just to make sure but got the same result both times. Is there an economical option to try to get my CYA down other than a water change? Paying for water here is pretty expensive. Thanks in advance.
 

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Well I just tried that and got the same result. The black dot is completely gone well before the water line even gets to 100. I tried the diluted test but got nearly the same reading. The water did rush out of the faucet and caused a little bit of the water to splash out of the bottle. I'm getting tired so I'll probably wait until early morning to check it again so I have a fresh set of eyes. Thanks for the link. If anything drastically changes with my results I'll post an update in the morning.
 

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Last time I checked a water truck is $1000 per load. I pay for water service at the house but I have no idea what they would charge me for using that amount of water. I noticed PoolMath says I need a 60% water change so I'll need to pay for a lot of water. I don't know anything about Reverse Osmosis but I'm guessing that's a filter system that needs to be added to my equipment?
 

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Ok, since I'm new to this and trying to educate myself on CYA, is my high CYA reducing the effectiveness of the chlorine which is causing the algae growth? I thought my chlorine readings would be lower with a high CYA. Or, does the test kit still show high chlorine but it's just not "as effective" as it would be with lower CYA?
 

tim5055

Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
10,425
Franklin, NC
Ok, since I'm new to this and trying to educate myself on CYA, is my high CYA reducing the effectiveness of the chlorine which is causing the algae growth? I thought my chlorine readings would be lower with a high CYA. Or, does the test kit still show high chlorine but it's just not "as effective" as it would be with lower CYA?
Correct, the high CYA makes the FC less effective. The FC still shows up on the test.
 

RoaringRam

Member
Jul 6, 2016
23
Mebane/NC
Yep I've read them. Based on that info, it seems the test kits will still show "x amount" of FC but it won't be as effective as FC with a lower CYA. One last question: Will doing partial water changes over time help lower the CYA or does it all need to be done at once? I'm just trying to spread out the cost of replacing the water if I can. Thanks.
 

tim5055

Mod Squad
TFP Expert
LifeTime Supporter
May 11, 2014
10,425
Franklin, NC
Yep I've read them. Based on that info, it seems the test kits will still show "x amount" of FC but it won't be as effective as FC with a lower CYA. One last question: Will doing partial water changes over time help lower the CYA or does it all need to be done at once? I'm just trying to spread out the cost of replacing the water if I can. Thanks.
Yes it will, but......

5 - 20% drain & fills replace less water than one 100% drain & fill

The problem you have is algae in the pool now. The high CYA will make it difficult/impossible to eradicate.
 

JesseSchmidt

Well-known member
Jun 19, 2015
230
Fairfield Twp, OH
Do you have city water? Cistern? Well? If city, call the water company and ask about filling a pool, they may not charge sewage on X amount of water if you tell them what you are using it for.

Edit: I just looked it up and our water company actually has "summer water usage" setup to automatically compare your summer usage to your average winter usage and assumes the extra is for watering the lawn/garden or the pool and deducts that amount from the sewage. So you just pay for the water. Not bad!