Yellow Algae Or Calcium Scaling?

[TexasPool128]

Does this look like yellow mustard algae or calcium scaling? It’s on the walls and some on the bottom.

 

[TexasPool128]

Then I have this white buildup on the waterfall rocks. Some of it appears to be calcium buildup but some is glossy, almost sponge-like in appearance, but very firm and unable to be easily scraped off. Is this calcium?

 

[TexasPool128]

All readings are good but CH is on the higher side but not ridiculous. CC is 0. Can I have algae and have a CC of zero?

 

[red-beard]

Most of the time I had Mustard Algae, it looked powdered and generally built up in the shadows (south-side) of the pool. It also built up in the areas where the circulation wasn't great.

Try brushing it. If it sweeps away, it could be algae. If it stays, you do not have algae.

 

[TexasPool128]

It definitely stays on, even using a stainless steel brush. I’ve brushed it dozens of times and it won’t budge.
I forgot to add the pH got really high for quite a while during and after our big freeze we had this year.

 

[Rancho Cost-a-Lotta]

Stains in Your Pool

The stained pool is beyond embarrassing. Our in-depth Guide to remove stains in your pool will help you to remove the stains and prevent them in the future.

www.troublefreepool.com

 

[Texas Splash]

I'm leaning towards calcium, at least for the waterfall area. If you can scrape some pieces off, pour some acid on it. If it fizzles, you have calcium.

 

[red-beard]

If it is stains, then it is not Mustard

 

[mknauss]

Last year your thread you had 'grit' in the pool with high CH. Did you drain the pool?

The color of the walls looks like copper, has any copper containing products been used.

 

[TexasPool128]

Stains in Your Pool

The stained pool is beyond embarrassing. Our in-depth Guide to remove stains in your pool will help you to remove the stains and prevent them in the future.

www.troublefreepool.com

Unfortunately that page has no pics so doesn’t help me but thanks anyways!

Last year your thread you had 'grit' in the pool with high CH. Did you drain the pool?

The color of the walls looks like copper, has any copper containing products been used.

Nothing has copper that has been in or pertains to the pool. The grit is all gone. I never drained it and never figured out what it was but it’s all gone on it’s own.
I can scrub a small area pretty hard quite a bit and it does remove a portion of whatever it is off the wall but not completely.

 

[TexasPool128]

This sounds like it may be my issue. I have a constant onslaught of brown dirt blowing in the pool.

“Brown cloudy stains​

are often caused by calcium carbonate capturing either dirt, metals or copper as it forms its crystalline lattice structure. Calcium can appear in the form of a thin calcium film that covers dirt or metal stains on the pool interior. Although calcium carbonate is always white, in this case, it presents as brown or grey because the dirt discolours the calcium carbonate making it appear brown. Therefore, this type of staining cannot be removed with treatments such as chlorine or firm brushing because the calcium film over the surface ‘shields’ the staining.”

Thoughts?

 

[Texas Splash]

Thoughts?

It is true that calcium can shield something underneath, even organic. So treatment can be a bit trickier. But knowing exactly what you're up against will be job #1. Testing those deposits at the waterfall for fizzling could be one step. You don't have Poolmath testing logs linked to your profile, and I don't recall seeing a full set of test results in this thread, so a full set of test results would be valuable as well. Then we might be able to help give you some reliable steps to take.

 

[TexasPool128]

FC 6.5
CC 0
pH 8.2
TA 60
CH 1280
CYA <30

CH is way high so my only option is to drain 85% of the water (according to PoolMath)? With CH being so high and CC being zero, it’s safe to say its
Wife blindly puts in chlorine and MA so those numbers are off.
Thanks.

 

[Texas Splash]

The very high CH and elevated pH are a recipe for scale. Adding chlorine and acid doesn't hurt, in fact you need more acid to lower the pH. But as soon as you can you need to exchange water to lower that CH. Be prepared to do it in stages as you never want to lower too much water and risk popping the pool out of the ground.

 

[TexasPool128]

The very high CH and elevated pH are a recipe for scale. Adding chlorine and acid doesn't hurt, in fact you need more acid to lower the pH. But as soon as you can you need to exchange water to lower that CH. Be prepared to do it in stages as you never want to lower too much water and risk popping the pool out of the ground.

When I do drain it, what’s a good method for getting the scale off the walls without doing an acid wash? I’ve called all the local pool companies and none are taking on new jobs right now as they’re all booked up doing repairs from our bad winter storm and existing customers.

 

[red-beard]

With a CH that high, test your fill water and report it here.

 

[TexasPool128]

Tested the fill water and it’s 140ppm.

 

[red-beard]

Yep, your calcs are correct. ~85% (82% by my spreadsheet). 85% would be good.

Where in N. Texas are you? In Houston, with the pure clay ground, I have successfully fully drained my pool, multiple times (4 times, I think). If your ground has a high water table, you might float the pool. I don't think that will happen here.

That seems incredible. Your pool is barely 2 years old and the CH went over 1200? Seems too much from a make up water standpoint. That would be 7 fills! Well, 7 fills past ~300. Did a pool company add a whole bunch of calcium to the pool? Or use extensive Cal-Hypo for chlorination?

 

[TexasPool128]

We live in north Texas. The pool sits in about 1’ black clay then about 2’ of sand then the bottom is celiche. When they were digging the pool it appeared the whole lot was raised by the home builder back years ago using sand. They’ve already drained and filled it once when they replaced the first plaster job.
I’m not sure what the builder used. The plaster we have now is 1 year old. The original 1 year old plaster got a crack/leak in the bottom so they redid it spring of 2020. Our water is supplied by a “Special Utility District” so no telling how often the water is altered or changed.

 

[red-beard]

We live in north Texas. The pool sits in about 1’ black clay then about 2’ of sand then the bottom is celiche. When they were digging the pool it appeared the whole lot was raised by the home builder back years ago using sand. They’ve already drained and filled it once when they replaced the first plaster job.
I’m not sure what the builder used. The plaster we have now is 1 year old. The original 1 year old plaster got a crack/leak in the bottom so they redid it spring of 2020. Our water is supplied by a “Special Utility District” so no telling how often the water is altered or changed.

North Texas as in Dallas area or Panhandle? The ground is very different. And the description of your raised lot makes is even less likely you will have a ground water floating issue.

If the pool has been fully drained before, the chance of it floating is remote. Using 2 sump pumps (1/6 and 1/3 hp), I can drain my 25K gallon pool in 12-14 hours and refill in 8 hours using the pool makeup line plus two 3/4" hoses. Using just the 1/3 hp pump and my makeup line, I expect you could drain and refill your pool completely in 24 hours or less.

On the other topic, On your MUD water supply, they usually have testing every few years that is published on-line.

Wait, so the pool was drained and refilled in the past year and the CH level is 1200+? Something weird is going on to get that high a level. Very weird.