What to aerate with?

Postby **Henry_R** » Sat 10 Sep, 2011 11:52

Denniswiseman wrote:Hi

I have high TA

Because we are in the UK and have to heat the pool we keep it covered through the night and don't want to cool the water by spraying it
I have been looking at a pond aerator http://www.water-garden.co.uk/shop_more ... no=V125099 to aerate while the pool isn't in use

The manufacturers say "Thank you for your e-mail. For the first question, this could be done but all our products are mend for pond hobby use and not for swimming pools. Our products don’t have any approval for this kind of purpose and we won’t advise it."

Obviously they can't approve of it for legal reasons.

Can anyone else see a problem with using this intermittently while the pool is not being used

That looks like it would work. What about it's power cord length? A pond is not usually very deep as a pool is.
That would be the deciding factor.

Postby **Henry_R** » Sat 10 Sep, 2011 11:56

chem geek wrote:Your pH is rising because your TA is too high. 120 ppm is NOT the target you should be shooting for. When using hypochlorite sources of chlorine, it should be far lower, usually no higher than 80 ppm and if your pH is still rising too quickly at that TA you could go even lower, but for now get it down to 80 ppm using the procedure I gave to you. If you lower the pH to 7.0, then it should rise reasonably quickly so that you can add more acid to keep it down -- the early phase of lowering the TA will be faster and easier. Right now with the pH rising so quickly, you don't really need to worry about aerating -- you should instead be adding acid more frequently to keep the pH down at 7.0 during this process. As the TA gets lower, the rate of pH rise will slow down so the process takes longer, but then again that's near the end of where you need to be since the goal is to slow down the rate of pH rise.

The TA moves a little with the pH so don't worry about the "bounce" of it. It's just way too high and is causing your pH to rise, period. Remember that it takes 25-1/2 fluid ounces of full-strength Muriatic Acid (31.45% Hydrochloric Acid) to lower the TA by 10 ppm in 10,000 gallons. Use The Pool Calculator to calculate dosages but you won't be adding the total amount of acid to lower the TA at once, but instead add enough to get to 7.0 pH during this TA lowering process (again, read the procedure I linked to).

Finally got some dry acid after pH was over 7.8 for three days the finally went to 8 and above. :evil:

I had to beg for the acid or I'd've had to buy it myself. :problem:

I dosed it last night in two steps, one to get it to 7.8 and then a second dose. pH is down to 7.2 this morning with TA at 110. I still don't have the means to aerate so I'll have to let pH rise and add some more over time.
Not much choice. I'm not going to be given the funds to get a pump for making bubbles and 7.2 is at least swimable though we've had a downshift in night temperature and the water is too cold to swim the last last week.

Denniswiseman · Postby **Denniswiseman** » Sun 11 Sep, 2011 14:35

Hi

This air pump has a 1.5m cable which doesn't go into the water and 2 x 5m air hoses
I do believe that these can be extended

There are cheaper air pumps around, I chose this one because of the output 6000 LPH

I might add that it wont be running while the pool is being used for safety sake

Postby **Henry_R** » Tue 13 Sep, 2011 09:35

Denniswiseman wrote:Hi

This air pump has a 1.5m cable which doesn't go into the water and 2 x 5m air hoses
I do believe that these can be extended

There are cheaper air pumps around, I chose this one because of the output 6000 LPH

I might add that it wont be running while the pool is being used for safety sake

Ah! 3 feet(US) is plenty of length.

Postby **Henry_R** » Tue 13 Sep, 2011 09:47

chem geek wrote:Your pH is rising because your TA is too high. 120 ppm is NOT the target you should be shooting for. When using hypochlorite sources of chlorine, it should be far lower, usually no higher than 80 ppm and if your pH is still rising too quickly at that TA you could go even lower, but for now get it down to 80 ppm using the procedure I gave to you. If you lower the pH to 7.0, then it should rise reasonably quickly so that you can add more acid to keep it down -- the early phase of lowering the TA will be faster and easier. Right now with the pH rising so quickly, you don't really need to worry about aerating -- you should instead be adding acid more frequently to keep the pH down at 7.0 during this process. As the TA gets lower, the rate of pH rise will slow down so the process takes longer, but then again that's near the end of where you need to be since the goal is to slow down the rate of pH rise.

The TA moves a little with the pH so don't worry about the "bounce" of it. It's just way too high and is causing your pH to rise, period. Remember that it takes 25-1/2 fluid ounces of full-strength Muriatic Acid (31.45% Hydrochloric Acid) to lower the TA by 10 ppm in 10,000 gallons. Use The Pool Calculator to calculate dosages but you won't be adding the total amount of acid to lower the TA at once, but instead add enough to get to 7.0 pH during this TA lowering process (again, read the procedure I linked to).

I finally got pH to stay at 7.2 and TA 100ppm. I'm going to have to leave them alone for now unless pH goes back up. Since I was given dry acid (now I wish I hadn't offered it as an alternative and stuck with the MA given the posts here against dry acid, but I can't go back now I was lucky to have been given what I was given) and I don't want to build up sulfates too much so I'm going to be cautious in not over using it pH=7.2 and TA=100 is fine. I've added about 5-6lbs of the dry acid since Friday so hopefully that won't push things too much. We cannot backwash very frequently here in Houston since we're restricted from refilling our pool once it's level is lowered. Unless the pressure goes up I've not been backwashing at all. That might be counterintuitive, but it's a necessity given the water issue. I used some cal-hypo yesterday so I'll probably vacuum soon which will necessitate backwashing anyway
but that'll be the first time in over a week.

Postby **chem geek** » Tue 13 Sep, 2011 12:32

Good news. You certainly don't need to keep the pH that low now that the pH is more stable. If it settles in close to 7.5 you should be fine. Great job!

Postby **Henry_R** » Wed 14 Sep, 2011 01:55

chem geek wrote:Good news. You certainly don't need to keep the pH that low now that the pH is more stable. If it settles in close to 7.5 you should be fine. Great job!

I hope it will go up, yes. I've been checking daily so I'll hope it's good in the morning.

Denniswiseman · Postby **Denniswiseman** » Mon 24 Oct, 2011 09:47

Is there an upper limit to increase your PH with aeration
Having successfully used it to reduce my TA I've been trying to increase PH but it doesn't seem to budge

Postby **chem geek** » Mon 24 Oct, 2011 12:53

It's not so much of an upper limit as a slowing down of outgassing as the TA level gets lower or the pH gets higher. This is shown in this chart. If you have trouble raising the pH by aeration, then that means you've gotten your TA level down to a point where the pH is much more stable which is a good thing. If you want to then raise the pH and aeration isn't doing it, then you can use 20 Mule Team Borax to do so as it will raise the pH with half the rise in pH compared to a pH Up (sodium carbonate) product. There shouldn't be any need to lower the TA level further once you reach such a point of fairly stable pH.