Persistant Algae

[JMPool99]

Ok GREAT. So you're roughly testing at the low FC point of the day. The SWG lost ground from 10A to 2P and runs 5 to 6 hours after you test, then again in the morning before the sun gets crazy again.

In this case, maybe you're 10 or 20 off on the CYA because we're friends and can be honest with each other about that test. . Normally, being 10 or so off isn't enough to swamp you, but maybe the TX sun tips the scales.

Or something is killing production occasionally and it's not noticed if you miss testing that day.

Or there is algae hiding in plain sight that was missed with a previous SLAM. Ladder rails, light niches, skimmer foam, auto fills, etc could be reintroducing old algae and the SWG is keeping it mostly at bay.

Is there environmental debris on anything else like your cars ? We started here about a month ago and I'm still getting dustings some days. It's probably time for you now.

I am experiencing the same EXACT this as the Original Poster here. CYA 50, but FC is always about a 7-7.5, yet I just got algae back again on my pool vac and hose port. My ph 7.7, CH 400, TA 80 are all consitently stable. I'm stumped.

My only guess is what you're saying here and that there must be some residual algae somewhere that my FC is keeping at bay until FC drops to lowest of mybe a 5 (I test daily). I have SLAMMED twice and this garbage keeps coming back.

 

[Newdude]

Hey JM !!!

I split you off so that we can zero in on your specifics without detracting from the OPs saga over in the other thread.

My ph 7.7, CH 400, TA 80 are all consitently stable

Good to know but those aren't in play here.

CYA 50, but FC is always about a 7-7.5,

Before you dose ?

My only guess is what you're saying here and that there must be some residual algae somewhere that my FC is keeping at bay until FC drops to lowest of mybe a 5 (I test daily)

How buck wild did you go scouring every inch ? Repeat slams are often due to missing a spot(s) and it starts blooming again in no time. Every last inch is suspect.

 

[JMPool99]

Hey JM !!!

I split you off so that we can zero in on your specifics without detracting from the OPs saga over in the other thread.

Good to know but those aren't in play here.

Before you dose ?

How buck wild did you go scouring every inch ? Repeat slams are often due to missing a spot(s) and it starts blooming again in no time. Every last inch is suspect.

Thanks for the reply! I forgot to mention my CC is always 0 and I'm passing OCLT - so weird. I think you're right that I'm missing some algae somewhere. Let me ask... if the FC gets up high enough wouldn't anything that comes in contact get killed? That's whole idea right... :- ) ?

And yes, my FC is always about 7-7.5 -- I keep it on high side. I just dumped in a couple gallons to get my up to FC 20. I just went through this in June though. Overall my water looks great. I'm on top of regular filter changes, and water and pool LOOK good. So... what the heck, right?!

 

[Jimrahbe]

JM,

You should only need to SLAM once.. If you have to keep SLAMing, then it is not being done correctly...

My suggestion would be on your next SLAM, use the SLAM level for a higher CYA than you think you have. And.. go for two extra days past when you think the SLAM is done.

Make sure you are brushing everything and check out hidden places, like behind your lights or under ladders etc.

The basic problem is that an FC of 7 to 8 is enough to keep algae from starting, but it is not enough to kill algae that is still in the pool.

Another thing is to make sure that when you test your FC you do it at the lowest level it will be all day. If you only dose Liquid Chlorine at say 10 am, you need to ensure that at 9:59 it is 7 or 8 ppm..

This is one of the great things about a SWCG.. It can basically maintain your FC at a pretty constant level day in and day out.. I would just as soon fill my pools in with dirt, if they could not be saltwater pools.

Thanks,

Jim R.

 

[Mdragger88]

Let me ask... if the FC gets up high enough wouldn't anything that comes in contact get killed? That's whole idea right... :- ) ?

Algae forms biofilms to protect itself from chlorine - even high levels.
Brushing breaks through this barrier to allow the chlorine to kill the algae. Brushing is key to eradicating algae.
You said you have black algae on your pool stuff. You should soak & scrub those items. Is it anywhere else on the pool surface?
Can you smear some of it on a paper towel to see what color it is?

 

[Newdude]

if the FC gets up high enough wouldn't anything that comes in contact get killed? That's whole idea right... :- ) ?

Some areas like the light niche or ladder rails get minimal circulation, even when you do everything else right.

 

[JMPool99]

Algae forms biofilms to protect itself from chlorine - even high levels.
Brushing breaks through this barrier to allow the chlorine to kill the algae. Brushing is key to eradicating algae.
You said you have black algae on your pool stuff. You should soak & scrub those items. Is it anywhere else on the pool surface?
Can you smear some of it on a paper towel to see what color it is?

Nothing black -- just some mustard yellow. And, you're right about biofilms... happens in humans too so certainly could see how this would happen. So, looks like I really need to brush the heck out of everything! There has to be some residual that's slowly coming back.

 

[Newdude]

You mentioned the vac hose and while it may not be the only place hurting you, it's a likely place with all the corrugated grooves. You'll want to get a 50/50 bleach mix swishing though there. If you can tie something fluffy to a string and pull it through it would be even better once it's soaked a while.

Take a ziplock sandwich bag and tie the string to it making the baggie look like a bow tie. Stick it in one end of the hose and use a shop vac to suck it through.

 

[Mdragger88]

Nothing black -- just some mustard yellow. And, you're right about biofilms... happens in humans too so certainly could see how this would happen. So, looks like I really need to brush the heck out of everything! There has to be some residual that's slowly coming back.

If you suspect recurrent mustard algae you do the
SLAM Process to completion (meeting all 3 exit criteria) then proceed to the MA protocols for 24hrs & thereafter maintain MA minimum for some time (the amount of time is different for everyone)

Mustard Algae

Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.

www.troublefreepool.com

 

[JMPool99]

Thanks for sharing the MA FC levels -- I need to go add way more chlorine! The post your shared (below) describes exactly what I'm going through. Even at high end of normal FC range, this junk comes back slowly over a couple months.

Mustard Algae

Today We are going to show you how you can get rid of mustard algae in your pool. By following the steps in this guide and with no expensive chemicals.

www.troublefreepool.com

Also -- good tips on vac hose. Honestly, I'm about to give up on the vac -- seems it does so little. I may go robot, but that's a whole other discussion and I've read countless post on that debate!

Curious -- any thoughts on common sources of mustard algae? Is it prevalent, or does it get introduced by swimmers, blown in? Just wondering!

Appreciate all the responses... off to dump some more chlorine in.

 

[duraleigh]

There is roughly about 7,000 species of algae. Probably many of species of mustard algae that popuLate the earth.

The source for ALL algae is essentially the earth........it is everywhere.

Just stay focused on algae as a generic BATTLE and remember chlorine is the key to defeat ALL of it!

 

[Mdragger88]

As @duraleigh said - most is just regular ole algae (it can be many colors).
They key is thoroughly doing the
SLAM Process with regular slam level fc
FC/CYA Levels
until you pass all 3 end of slam criteria
You are done when:
CC is 0.5 or lower;
You pass an Overnight Chlorine Loss Test
AND
The water is clear.
(Crystal Clear w/no algae dead or alive)

Do ALL the things
*Check & scrub every nook & cranny where algae may hide {light niches, steps (inside & out), drain covers, ladder handrails, skimmer throats/weirs, abandoned lines, autofill, overflow drains, seam flaps, etc.}
*If water can go there, algae can thrive there.
*Run slam level water through all water features & lines for at least a couple hours a day during the SLAM Process.
*Brush & or vac daily (this breaks up biofilms that algae uses to protect itself from chlorine)
*Backwash/clean filter when pressure rises 25%over clean pressure.
Then if you have a suspicion of MA you go for the MA protocols for 24 hrs. This is more for insurance & the final nail in the coffin. You don’t just jump to the MA part.

 

[JMPool99]

Yep! Doing all those things now! FC holding strong at 32 since raising it to that level yesterday. Water has been crystal clear throughout. I removed all pool vac equipment and wiped down with bleach and then hosed off.

The algae on the pool vac hose door (on the pool wall) had algae but now since hitting FC 32 was gone before I wiped / brushed it (I still cleaned it anyway).

Crossing my fingers this all does it... going to keep the FC up for a bit!

 

[Mdragger88]

Yep! Doing all those things now! FC holding strong at 32 since raising it to that level yesterday. Water has been crystal clear throughout. I removed all pool vac equipment and wiped down with bleach and then hosed off.

The algae on the pool vac hose door (on the pool wall) had algae but now since hitting FC 32 was gone before I wiped / brushed it (I still cleaned it anyway).

Crossing my fingers this all does it... going to keep the FC up for a bit!

To clarify- you passed all 3 end of slam criteria @ 20ppm fc BEFORE raising to MA slam level? (Which is only 30ppm for a cya of 50)

 

[JMPool99]

Yep. I did standard SLAM first and passed all. I didn't even know about the MA SLAM level until this thread. And yes, 30PPM is the target, but obviously nothing exact with all this stuff, so I ended up at 32 FC after adding what Pool Math recommended and I've been steady there.