First pool, water is clear but fiberglass is stained and lots of scale

[PoolDoc]

OK. You've got several options here.

1. We can get the water in shape to OPERATE, with no new scale, pretty easily. But, with that high calcium level, it's going to be hard to get it into a calcium-removing state. If want to just operate the pool, and let the scale go, you can lower the pH and aerate, till your TA is much lower, and you'll be fine.

2. To LOWER the calcium, you have two options. The first is simply to drain and refill. But, with a fiberglass pool, if there's ANY water in the ground, your pool can FLOAT out of the ground, destroying it. If you're on hillside, and the weather hasn't been soggy, you are probably fine. If you are in a flat or low area . . . be VERY careful! (Since you're in Las Vegas . . . it may not be an issue!)

3. Your second option is more complicated, but won't waste so much water. You can do a 'lime-softening' process, by adding a bunch of sodium carbonate, till the calcium precipitates, and then vacuum and filter it out. Doing this, you can end up with quite low calcium -- lower than the fill water -- and that will help you strip the scale. Here's the process:

+ raise your water level to the max -- if it's safe, raise it to spill over.
+ remove your cartridge from your filter
+ add a dose of PAC floccing agent
+ follow it with sodium carbonate till your pH > 10.0
+ mix, turn your pump off, and let it settle.
+ vacuum the floc to waste. (you may have to add T valve to enable this)
+ replace the cartridge filter, turn the pump back on
+ add muriatic acid till your pH is ~ 7.0, and begin aerating
+ use acid + aeration to strip carbonate alkalinity till your TA > 80 ppm
+ hold your pH at 7.0 - 7.2 till the scale is gone; try to keep the water level ABOVE the scale.

The last option is by far your best choice for removing scale and stains. And, it's not as much work as it sounds, but you will have to be careful to follow the process. To do it, you'll need several items;

+ Poly aluminum chloride floc
+ Wide range pH test strips
+ Washing soda from Walmart (yellow box, maybe 8 boxes?)
+ Muriatic acid from Lowes (gallons, maybe 4 gallons)
+ HEDP for post treatment

You can get the washing soda (soda ash, pH up) and muriatic acid locally and cheaply; I'll need to help you get the exact item on the other three products, if you're interested.

Given your fill water's condition, and the high evaporative rates, learning to do this might be worthwhile. You *should* be able to get lower calcium and alkalinity levels than you have in your fill water. I'm guessing you might need to do it every other year, to avoid scale, and I'm guessing water in Las Vegas costs enough so that this should be cheaper than draining and refilling. (I'm guessing total cost may be around ~$100.)

[MountainStone]

Wow, thanks for the in-depth info Doc. To help me choose a course of action, can you answer a couple of noob questions?

1. What is the disadvantage of high calcium hardness, other than the scaling on my fiberglass? You say I can just lower my TA and be fine; does that mean there are no adverse effects on my water treatment regimen or my pool equipment from a high (and increasing) calcium hardness?

2. It would cost me roughly $60 in water to drain and refill the pool, but I hate wasting water and I have no knowledge of the local water table so would be VERY hesitant to drain this fiberglass pool.

3. Your second option for lowering calcium hardness sounds pretty intense but I'm sure I could do it (I have a T-valve that has a capped threaded stub). How long do you think the pool would be out of operation? It is almost warm enough to swim here and we are looking forward to getting in our new pool for the first time in the next couple of weeks.

I really can't say 'thank you' enough times!

[PoolDoc]

1. Yes, you can do just that . . . as long as the scale doesn't bother you AND you don't get a heater or an SWCG. High calcium can cause problems with either one.

2. If you're in Las Vegas, you are probably pretty safe draining the pool. I'm assuming you on dry sandy soil? (I don't know; sorry, but Las Vegas has always been at the bottom of the list of places I'd like to go, just below Newark, NJ ) My only concern is that you'll STILL have high calcium, and have a hard time removing the scale.

3. You'd want to allow 2 weeks. I think it would be less, but I don't know for sure.

If you're ready to swim, and the scale isn't a problem, why don't you just lower the TA, and then make a decision this fall about whether you want to go further? This page will tell you how to do it: http://www.poolsolutions.com/gd/lowe...p-by-step.html

[MountainStone]

Doc,

I think I will take your advice and lower the TA of the pool for now without worrying about the high calcium and the scale. I just dropped my pH to 6.8 and pointed my inlets at the surface to impart some 'ruffling.' I think I'll pick up a couple of the little fountains that attach to the inlets to better aerate, as I will likely also need them to help lower water temps this summer.

I'll attack the calcium buildup at a later date. As you say, the soil here in the Las Vegas valley is sandy and full of caliche. The grade falls away from my neighborhood, so my little 5' deep pool is likely above the water table. I think all our drinking water comes from Lake Mead; there may not even BE a water table. Draining/refilling may be an option at the end of summer if I don't feel adventurous enough to try your method of precipitating it out.

Thanks for all the help!

[PoolDoc]

there may not even BE a water table

that's what I suspect!