calcium hardness/ metal control new to me, do I need them

Here is our reading from the pool store, we have a fiberglass pool.

TC = 5
FC = 5
Ph = 7
TA = 25
Calcium hardness 185
CYA 80
total dissolved solids = 600

This is the plan from the pool store-

Add 16 oz of metal control to stop staining - wait 24 hours

then add 7 lbs of total Alkalinity increaser (sodium hydrogen corbonate)
wait 24 hours

Then add Calcium Hardness Increaser 10 lbs one day and 10 pounds next day.

We've had the pool for one year and last year the chemicals stayed good. So I have never added metal control or calcium. Since we have a fiberglass pool do we need to add calcium? So I'm not sure if this is right, can I get some advice please.

Thanks

Quote:

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Originally Posted by karenib

Here is our reading from the pool store, we have a fiberglass pool.

TC = 5
FC = 5
Ph = 7
TA = 25
Calcium hardness 185
CYA 80
total dissolved solids = 600

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Boy! Do I HATE pool stores! Nowhere did they give you a metal read-out. TDS=600? So What? TDS is one of those scare-tactic measures, like Phosphates.

You have a very, very low TA, a fairly low pH, a surprisingly high (but manageble) CYA

My suggestion? Raise your pH to 7.3 to 7.6--use Borax. Raise your T/A to 80-100--use Baking Soda. Or, use Washing Soda (in the Arm 'n' Hammer YELLOW Box) instead of both Borax and Baking soda.

I think you need to shock your pool up to 20ppm--green may be metal, but with no metal read-out it's more likely algae. Your FC is the MINIMUM for a CYA of 80, but I think it's too low--the scale is vague--for CYA of 60-90, use an FC of 5-10 and shock to 20. You, at 80 are at the higher side, so FC of 8 or 9 should be your minimum.

Pool stores always come up with expensive solutions to problems. Try the basics first.

And, if our metal expert disagrees with me, she'll merely tell you to use a metal sequesting agent, but before you shock the pool.

My pool store said I needed 6 lbs of calcium hardness today also. I was also wondering if I needed it? I have never put it in before. All other chemicals were fine. It is a little clouldy for some reason.


Above ground vinyl 7500 gallon
80 calcium hardness
FAC 5
PH 7.2
TA 90
CYA 40

NO!! A vinyl pool does NOT need calcium added to it. I hope you didn't buy it. If you did, take it back.

No I didn't buy it. Thanks for the input I had no idea and thought I would ask here first. Thanks

You do need some calcium in a fiberglass pool, but I wouldn't add that much. You can just keep what you have, I usually keep my calcium at around l50 - 200. I usually keep my ph between 7.2 and 7.4. Raise your alkalinity to about 80, the way CarlD says. Don't worry about tds. Carl is right with a cya of 80, you need a minimum of 5ppms chlorine, and a max of 10ppms and to shock you need 20ppms. So you may not want to use any chorine pucks (trichlor), because that will add cya. You can use calhypo - it will add calcium to your water with it. Bleach won't add anything but salt - which won't do anything to your pool. If you don't have any stains, you don't need any metal out. If you do see some staining, then you need to use something that sequesters metals. Feel free to ask any other questions you may have.:)

My DH didn't want to wait,he wants to go swimming tomorrow and the guy said not to go in the water until the ph is higher. So he added 7lbs of alkalinity increaser only. I'll have to see if I can find a pool store to run a test tomorrow or monday to check my numbers again. We didn't add anything else.

just a note, the water is crystal clear and there were no stains on the walls...so we didn't have any problems - we just had the water tested to check the TA and ph.

That's fine. You should have the alkalinity between 80 - 100. Just don't add the calcium. You do have to add more chlorine - get it up in to around 8ppms, this way when people start to swim you won't go below 5. After a couple of hours of adding the alkalinity up check your numbers.

Thanks Marie. Do you think I should hold on to the bottle of metal control in case I do get staining. The rest of the chemicals are going back to the store :)

Karen

Quote:

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Originally Posted by karenib

My DH didn't want to wait,he wants to go swimming tomorrow and the guy said not to go in the water until the ph is higher. So he added 7lbs of alkalinity increaser only.

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Karen - You said you were trying to raise ph so you added alkalinity increaser. Ph and alk are not the same thing. You raise ph by adding Borax. You raise alk by adding baking soda. If your alk was already 90, then I hope adding the 7 lbs. of alk increaser doesn't raise your alk too much.

Yes, I would just hold on to the metal control until you see some stains forming. If you see a stain starting, then take the ph down to 7. - 7.2, and add the metal control. It should lift the stain off.:)