Getting rid of copper or balancing water at first?

[matali]

Hi everyone,

This is my very first post here.
We have been a pool owners for less than 2 weeks and everything is very new to us. I don't even remember all the pool parameters yet (sorry!), I will work on that.

And I am sorry I don't have water test results but I will have it tested tonight.

The pool inspection (before buying) mentioned high acidity (low pH) of the water. The previous owner (who had this pool for 8 years) opened the pool for us and balanced the water, so we started using it.
Last week the water seemed to be still acidic; the strip test showed low pH and low alkalinity.
We took the water to pool store and the test showed that the copper is high (also low pH + low alkalinity + low FC).

The pool store guy told us to look for any rust in the pool - (we found rust on skimmer screws) and he told us to buy the chelant agent (Metal Free).
According to him we should get rid of rust first (so replace the screws), then add chelant agent, and in the end take care of balancing water.

However I have some doubts/and questions:
1. Can rust from screws cause high copper levels? Steel screws mainly contain iron. So what copper has with it? Not sure if he tested for iron.
2. WHAT IS MORE IMPORTANT: balancing the water or adding chelant agent to bind the copper first?
3. Can copper presence influence balancing the water?
4. What is a safe level of copper for the pool (I mean if we want to use it)?

Thanks in advance for any recommendations/hints,

matali

 

[jmbradwell]

Welcome to TFP.

Pool store testing is very unreliable. I've taken three samples, taken at the same time, to three pool stores and got 3 completely different sets of results along with 3 different very expensive chemical recommendations.

You need to get a good test kit. The ones most recommended here are the TF-100 or the Taylor K-2006. The TF-100 is a better value.

For the metals and copper, I'll let one of the more experienced members chime in.

 

[Richard320]

Welcome!

What he said ^^^

We don't trust any of the other readings, why would we trust the metals testing? Bring a sample to another store, or the same store when someone else is working there. If they still say you have metals, then worry about it.

Copper in the water can come from corroded heater innards from acidic water, or copper-based algaecides. Depending on the other test results, you may want to do a partial drain anyway, and that will get rid of the copper, or lower it enough to where it's not a problem. Did they tell you what your CYA reading was? If the previous owner chlorinated with trichlor pucks, there's a really good chance the CYA level is so high as to be unmanageable. Trichlor pucks are also acidic, and a steady diet of them would account for acidic water, low TA, and corroded screws besides the astronomical CYA buildup.

 

[matali]

Thanks, guys.

Unfortunately I didn'tt manage to get to the pool store yesterday and the water is having a greener tint now, but for me it looks more like algae (clouding in the water when you brush it).
I will go to the pool store (different one) at lunch time so I hope I will get better test results. I will post them then.

I think the previous owner used trichlor pucks... What do you mean that CYA level is so high as to be unmanageable?
We just used a strip test and everything was below the norm (FC, pH, alkalinity and CYA).

Additionally we noticed a leak in the hose to the pump and now we don't know if we should turn it on/off. The pool service people can come on Monday - and we are afraid that everything will go astray..

Best,
matali

PS. Meanwhile I am going to order a test kit.

 

[Richard320]

I think the previous owner used trichlor pucks... What do you mean that CYA level is so high as to be unmanageable?
We just used a strip test and everything was below the norm (FC, pH, alkalinity and CYA).

To be effective, chlorine needs to be a certain percentage of CYA. If you look at this chart, you'll see that with really high CYA, you need to maintain really high FC, which is beyond the ability of most test kits to measure. High FC also interferes with the pH test, so if you have to maintain FC above 10, your pH test is always suspect. It's not uncommon to see CYA levels in excess of 200, which puts minimum FC at 14 or better. That's unmanageable.

Don't trust the test strips. Even if they're good and fresh, they won't be accurate enough for your purpose. Check out this comparison: http://www.troublefreepool.com/threads/81150-Taylor-2006-vs-aquacheck-strips-comparative-results

Additionally we noticed a leak in the hose to the pump and now we don't know if we should turn it on/off. The pool service people can come on Monday - and we are afraid that everything will go astray..

Best,
matali

PS. Meanwhile I am going to order a test kit.

A leak in the suction side of the plumbing will introduce air and the pump may lose prime and run dry and smoke the bearings or overheat and warp the pump housing. That needs fixing ASAP.

Ordering a proper test kit is a smart move. Be sure you get one of the suggested kits.

 

[matali]

To be effective, chlorine needs to be a certain percentage of CYA. If you look at this chart, you'll see that with really high CYA, you need to maintain really high FC, which is beyond the ability of most test kits to measure. High FC also interferes with the pH test, so if you have to maintain FC above 10, your pH test is always suspect. It's not uncommon to see CYA levels in excess of 200, which puts minimum FC at 14 or better. That's unmanageable.

OK, I got it now. If CYA is too high, then FC must be very high as well. So it is important to lower CYA in order to have maintain lower FC.

Don't trust the test strips. Even if they're good and fresh, they won't be accurate enough for your purpose. Check out this comparison: http://www.troublefreepool.com/threads/81150-Taylor-2006-vs-aquacheck-strips-comparative-results
A leak in the suction side of the plumbing will introduce air and the pump may lose prime and run dry and smoke the bearings or overheat and warp the pump housing. That needs fixing ASAP.

Ordering a proper test kit is a smart move. Be sure you get one of the suggested kits.

OK, just ordered TF-100. I will contact the pool guys to see the pump now.

Thanks!