recommend a filter please!

doughboyowner

Member
Jul 21, 2008
15
JasonLion said:
Getting one better/larger filter is much simpler than having two filters, and will work just as well as, or better than, two smaller filters. Moving the filter to the deep end of the pool might help just a little bit. For the best possible circulation, you want the return to point to the side and down into the deep end of the pool. There isn't any way to do that from the shallow end.

However, improving the filter will not solve any of the issues you have mentioned in any way.

One important distinction you are failing to make is between free chlorine (FC), combined chlorine (CC), and total (TC). Your test is measuring TC, which is the sum of FC and CC. CC is the part of TC that causes problems. FC does not cause problems. When FC levels are maintained appropriately the CC level will go to zero and the problems will go away.

Chloramines, and the trihalomethanes present in swimming pools, are all CC. You can get rid of them by using more chlorine and maintaining the correct FC levels. To do that reliably you need to have a test that distinguishes FC from CC, which your current test does not do.

I have one of the drop test things somewhere I just cant find it. Darn kids moved stuff trying to find pool toys last weekend.
 

Rangeball

Well-known member
May 25, 2007
785
doughboyowner said:
my question is should I put ONE big filter on one end or 2 smaller filters on both ends. is your response that you think 1 big filter would be better than 2 smaller ones?
Yes, I agree with Jason, one bigger filter versus 2 smaller ones.

What is the DE trick?
Add enough DE powder to your sand filter so that your pressure gauge shows a 1 psi increase. This puts a fine coat of DE on your sand which many claim promotes finer filtering.

I just had a full analysis done at the pool store over the weekend and he said everything was fine except my PH was a little low (he got 6.8 ) my results matched his that night so I am pretty sure that I have resolved the PH issue as it was just 7.2.
Did you just tell you it's fine or give you numbers? If you have complete numbers from him what were they? Do you know what testing methods he used?

chlorine we have 3 inch tablets in floaters at all times. We have 6 floaters w/ 3 tablets each.
shock I bought a 5 lb thing of shock from Meijers and have been using bleach ever since just to keep it up.
Do you have any idea what your CYA level is? Your problem is very very common trying to run a pool on trichlor, and I'd bet a donut your FC is inadequate for your CYA level.

By the way, chances are real good that your drop based kit isn't going to cut it either if it uses OTO for chlorine testing, which only measures total chlorine. You need a test that will show a breakdown, like the DPD/FAS test chlorine test. This is the Cadillac that will show you both levels AND work at higher chlorine levels.
 

frustratedpoolmom

TFP Expert
LifeTime Supporter
In The Industry
May 20, 2007
12,250
Key West, FL
Before you go to the trouble of reworking your filter, please consider the following.

Invest in a good test kit that can test for CYA and FC/CC (this test is called the FAS-DPD test). A good one is the Taylor K-2006 or the TF-100 test kit.

For your CYA of 40, your shock level is 16. See the CYA /Chlorine chart to understand the relationship.

Shock your pool until the FC of 16 holds overnight, which requires testing after shocking and again first thing in the morning to compare the 2 numbers.

Once your FC holds the algae is dead, and you can let the filter clear the pool. Since you stated you have cleared it before, then you already know your current filter is up to the challenge.

To prevent future green attacks and possible CC's (we don't know what your CC's currently are)....
For a CYA of 40 your minimum FREE chlorine level is 2.9. Your Target FREE chlorine level is 4.6. So you need to maintain a FREE chlorine level (this is not the same as Total Chlorine on the strips) of 3-4 AT ALL TIMES. If you let the FC drop below the minimum, algae will return, as it has with your pool. So at some point you must be letting your FC drop, correct? What has your FC level been at when the green water returns?

Lastly, trichlor pucks are acidic and will lower your PH. The proper PH level for your pool is about 7.5 to 7.6. Low PH can be irritating and also damage your pool equipment.

I hope this helps and I recommend you read the articles in Pool School so that you can begin to understand why we are making the comments about your water chemistry. Good luck.
 

doughboyowner

Member
Jul 21, 2008
15
frustratedpoolmom said:
Before you go to the trouble of reworking your filter, please consider the following.

Invest in a good test kit that can test for CYA and FC/CC (this test is called the FAS-DPD test). A good one is the Taylor K-2006 or the TF-100 test kit.

For your CYA of 40, your shock level is 16. See the CYA /Chlorine chart to understand the relationship.

Shock your pool until the FC of 16 holds overnight, which requires testing after shocking and again first thing in the morning to compare the 2 numbers.

Once your FC holds the algae is dead, and you can let the filter clear the pool. Since you stated you have cleared it before, then you already know your current filter is up to the challenge.

To prevent future green attacks and possible CC's (we don't know what your CC's currently are)....
For a CYA of 40 your minimum FREE chlorine level is 2.9. Your Target FREE chlorine level is 4.6. So you need to maintain a FREE chlorine level (this is not the same as Total Chlorine on the strips) of 3-4 AT ALL TIMES. If you let the FC drop below the minimum, algae will return, as it has with your pool. So at some point you must be letting your FC drop, correct? What has your FC level been at when the green water returns?

Lastly, trichlor pucks are acidic and will lower your PH. The proper PH level for your pool is about 7.5 to 7.6. Low PH can be irritating and also damage your pool equipment.

I hope this helps and I recommend you read the articles in Pool School so that you can begin to understand why we are making the comments about your water chemistry. Good luck.

AS far as why I am concerned w/ my filter I guess I wasnt really clear. (I didnt realize you all would jump all over my chemicals!) After the shallow end gets clear and the deep end is still green the filter starts blowing green gunk BACK into the pool. Which then makes the shallow end green again.... yes I backwashed it and yes it still blew the green Crud back in. THAT is why I dont think that this filter is enough for this pool. My husband thinks our sand is bad (new last summer) I think the filer is just not up to the challenge of clearing ALL of the pool. SO I am wondering if putting a second set up on the deep end would clear the deep end since this one only seems to be clearing the shallow end....

Does that make more sense?
 

Rangeball

Well-known member
May 25, 2007
785
What model pump and filter do you have?

With a small filter and larger pump, it's entirely possible your GPM flow from the pump exceeds your filter max, leading to channeling and poor filtering. If you suspect this is the case, you could put a valve on the return side of the filter to reduce the flow. But I still think one larger filter is better than two smaller ones.

Another point, the algae coming out of your filter back into your pool wouldn't be green if it was dead.
 

doughboyowner

Member
Jul 21, 2008
15
Rangeball said:
Another point, the algae coming out of your filter back into your pool wouldn't be green if it was dead.
THAT I had not thought about....


I will look at the pump and filter next time I wander out there....its a pretty far walk and my preggo feet are swollen!
 

doughboyowner

Member
Jul 21, 2008
15
ok I found my test kit but the darned drops expired last summer....I tried it anyway and both the FC and the TC came out at 10 so I am pretty sure I need new drops cuz that dont make sense to me!
 

frankthailand

Well-known member
Apr 22, 2008
152
Thailand
doughboyowner
Hello according to my calcs your pool holds about 30,000 gallons, so you could [ i would]
go for a larger filter, always, when it comes to filters, the bigger the better.

Also IMHO the guys here are basically saying that test strips and pool shops are not accurate. [try 3 shops and compare, for sure they will all be different] Of course you are worried about your children, that is why these guys are trying to help with the water balance question.

So that is why they want to know your numbers, and the only way to get accurate readings is with a good test kit. IE the TF100, or the taylor K2006 test kits

we all want to help the lad have a happy swimm :-D
Frank
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
The Taylor K-2005 includes the DPD chlorine test. The Taylor K-2006 and TF100 contain the FAS-DPD chlorine test. There is more detail about DPD vs. FAS-DPD here.
 

wmshay6

Well-known member
Jun 21, 2008
149
Central MD
Doughboy Owner-

Please don't think these folks are "jumping all over your chemicals".

The facts of the matter are

1) you came here asking about a larger filter and describing a problem you are having with your pool.

2) You are using Tri-chlor tablets (ALOT of Trichlor tablets- there are 18 of them in your floaters!) which are known to cause the problems you are describing. (IMHO there is NO WAY you have a CYA of 40 if you are using floaters with that many pucks in them for any length of time.)

3) You have explained to us that your son's Asthma is triggered by the pool. This triggering of Asthma is a medically documented fact that occurs when there are high levels of combined chlorine. This was pointed out in the article mentioned earlier.

4) Yours pH requires ALOT of upward adjustment (presumably due to heavy use of the Chlorine pucks in your floaters)

All of the items in #s 1-4 are leading the folks here to believe that your problem is from OVERstabilization with a resulting low free chlorine residual and HIGH level of Combined Chlorine. No amount of additional filtration will help that. The assumption is that you have a CHEMICAL problem, not a FILTERING problem. And trying to fix a chemical problem with additional filtration is like hunting for bears with a fishing pole. It ain't gonna work.

These people are trying to help you solve a problem with your pool. The short answer is your filter idea will NOT solve the problem long term. But you can do it if you want to. However, it involves cutting your liner and pool wall and installing the new filter. This won't hurt anything except your pocketbook for the increased expense of running the additional pump. And once you do it, there is no going back.

Please don't take offense, but I have a few questions:

1) Do you have a test kit that will test for FC, TC, and CC independently of each other?

2) Do you know what the difference is between FC, TC, and CC? When the people here post the acronyms FC, TC and CC, do you know what they are asking?

3) When your son's asthma is triggered, is there a strong chlorine smell around / near the pool? (Sometimes? Always? Never?)

4) Where do you live ? What I'm getting at is do you winterize your pool by partially draining it each year? Or does your pool stay filled throughout the winter months with no appreciable loss of water?

The people here are pointing at your chemicals as the source of the problem. Therefore, getting the chemical issue resolved will solve your problem. You want to add additional filtration. That certainly won't hurt anything. But you asked these folks advice and their advice (which I agree with) is that it also won't HELP matters as you have described them. At least not long term.

I have three kids with asthma that ALL swim daily in a chlorinated pool. You CAN have a clean pool that your son can enjoy without adding the additional filter. But you have got to stop and listen to the advice being given.

Not trying to be rude, just trying to be frank. I posted four questions above- the answers to those four questions will go a long way into the people here understanding where you are coming from.
 

launboy

Well-known member
Jun 15, 2008
582
S.E. Wisconsin
As for the filter part, you said there are openings for a filter at both ends of the pool. Is there any way you can run the return line down to that end of the pool? Then the skimmer will be in the shallow end and the return in the deep end so the water will travel across the pool. That way the filter won't only clean half of the pool.

HTH,
Adam