Backwash multiple times in a row

[otherguy]

Is it common to have to backwash multiple times in a row? Hooked up the filter for the first time and have started running it to get the pool ready. I noticed that after backwashing and rinsing that it will run fine for a while (not long) before the pressure drops from the return, and so I backwash again. Now I started backwashing multiple times in a row, is that normal? I backwash until clear, rinse, then backwash again until clear, rinse. I do this about 3 times, then put it back on filter.

The water coming out is reddish at first from the dead algae that was there from winter I am guessing, but started shocking it to see if that helps.
My TF-100 kit came in, just haven't gone through the instructions yet to use it. Anyway, just wanted to know if backwashing multiple times happens sometimes until things get cleared up.
Thanks

 

[MITBeta]

Clogging filters is a common sign of an algae problem. Break out that test kit and post up some results.

 

[otherguy]

Clogging filters is a common sign of an algae problem. Break out that test kit and post up some results.

thanks, I will post numbers tomorrow, just to make sure the water has had 24 hours to settle down from the treatment.

 

[MITBeta]

You only need 15-30 minutes of mixing before testing.

 

[otherguy]

You only need 15-30 minutes of mixing before testing.

Cl/Br test was .5
ph was 8.2

FC 0.5
CC 0.5
TC 1.0
CH 250
TA 100
CYA 37-40 (was kind of hard to tell as I was looking really hard for that black dot)

Now that I have these numbers, what is the best way to tell what to do or what to add?

 

[otherguy]

…. And those numbers are after using a whole bottle of liquid chlorine yesterday, if that matters.

 

[MITBeta]

Can you fill out your signature so that we know what kind of pool and equipment you're dealing with?

Next step is to run an Overnight Chlorine Loss Test: You should add enough liquid chlorine tonight after the sun goes down to get the FC level to around 10ppm. Measure 30 minutes after adding to figure out what the actual number is. Then, first thing in the morning, before the sun shines on the pool again, get another FC reading. If the difference is >1ppm, it's time to follow the SLAM Process.

By the way, you don't need to test Chlorine using the comparator attached to the pH guide. Only use the FAS/DPD powder and drops to test.

 

[otherguy]

Can you fill out your signature so that we know what kind of pool and equipment you're dealing with?

Next step is to run an Overnight Chlorine Loss Test: You should add enough liquid chlorine tonight after the sun goes down to get the FC level to around 10ppm. Measure 30 minutes after adding to figure out what the actual number is. Then, first thing in the morning, before the sun shines on the pool again, get another FC reading. If the difference is >1ppm, it's time to follow the SLAM Process.

By the way, you don't need to test Chlorine using the comparator attached to the pH guide. Only use the FAS/DPD powder and drops to test.

pool is an Intex 18x52

 

[MITBeta]

pool is an Intex 18x52

Great! Please put that in your signature along with the pump, filter, heater (if any), test kit, and anything else that might be pertinent to know about your pool. It will help in the long run.

Thanks!

 

[otherguy]

Great! Please put that in your signature along with the pump, filter, heater (if any), test kit, and anything else that might be pertinent to know about your pool. It will help in the long run.

Thanks!

I was finally able to run the overnight test. I didn't have any chlorine to speak of from my first test so I added lots, probably too much to be honest, but I wanted to make sure I got readings.
The number dropped 10 from the overnight to the morning.
I read about the SLAM process and added stuff to lower the pH level because it was too high.

I will say the pool is somewhat looking better, it went from having a reddish algae color to now be cloudy, which I will say is what it was most of last year (our first year), we never really got the pool clear, it always had a cloudiness to it.

Now I am running the filter but still concerned that I have to backwash so often. Last year (the first year) I could run it for over 12 hours without having to backwash, but now I am lucky if I get 1 hour before there is a noticeable difference in the pressure. Maybe I need to take the top off the sand filter and do some sort of manually cleaning?

I have the Intex 2800gph filter, which is a step up from what the pool came with.

 

[MITBeta]

Even the upgraded filters for Intex pools tend to be undersized. Your filter is working, it just has a lot of work to do. You must keep up with the SLAM Process through to the 3 exit criteria. Eventually, the filter won't need to be backwashed as frequently, but you'll have to babysit it for a while.

You might want to consider whether it will be cheaper and easier for you to drain and refill. It will still require you to SLAM once refilled, but this should go very quickly.

 

[otherguy]

Even the upgraded filters for Intex pools tend to be undersized. Your filter is working, it just has a lot of work to do. You must keep up with the SLAM Process through to the 3 exit criteria. Eventually, the filter won't need to be backwashed as frequently, but you'll have to babysit it for a while.

You might want to consider whether it will be cheaper and easier for you to drain and refill. It will still require you to SLAM once refilled, but this should go very quickly.

Finally the FC came down to 16 from 23 this morning, which 16 is supposed to be the slam level, so that is good.
Also checked pH and it has came down.
my CYA was still around 40, so based on that link the SLAM process should work.

From what I can tell on the links you provided I just have to keep watching it and keep the FC around 16 and just keep cleaning the filter as needed. At least now I feel more comfortable to get in the pool with a brush and stuff to try and clean it.

 

[MITBeta]

Don't worry about testing for anything other than FC and CC until SLAM is complete. But it looks like you have the process down.

 

[otherguy]

Don't worry about testing for anything other than FC and CC until SLAM is complete. But it looks like you have the process down.

Just wanted to give you an update and ask couple of last questions. I have kept the FC above 16 for days now and finally the water has cleared, not sure if its completely done or not but I can see the bottom now and the cloudiness seems to be gone.
I still have the overnight test to run so I am keeping it above 16 today and will test tonight and tomorrow morning.

If that has a lost of 1ppm overnight and the water is clear it sounds like I am done from the article.
Questions:
So, is now all I have to do is maintain a normal FC which is 5-7 I believe?
How often do I need to do the test, any of them, FC, CC TC, CH TA CYA, do I need to do them all if I do one or are different test required different intervals?
Just trying to figure out how often and which ones to run test throughout the summer.

Thank you for all your help @MITBeta

 

[MITBeta]

You're done if:

• CC is 0.5 or lower;
• You pass an Overnight Chlorine Loss Test
• Pool is clear (How clear is TFP?)

How often do I need to do the test, any of them, FC, CC TC, CH TA CYA

FC: daily until you know your pool well, and then maybe every other day
CC: weekly or if you suspect something
TC: never - this isn't something you can measure
pH: daily to bi-weekly until you know your pool, then weekly
CH, TA, CYA: weekly until you know your pool, then bi-weekly to MONTHLY or unless you are expecting a change

So, is now all I have to do is maintain a normal FC which is 5-7 I believe?

Follow the FC/CYA chart. To make sure FC stays above target. Try never to let it get to minimum.

Show us pictures of your TFPool!

 

[otherguy]

Show us pictures of your TFPool!

Here are some pics of the pool. I think I have the water testing down now, but know have another issue. I will ask you here but probably start another thread too.

The water level keeps dropping and I can't figure out why yet. The first year we had the pool, last year, this happened too but eventually stopped, it was like the pool was stretching itself into shape and eventually stopped and the water level stayed.
The pool was up all winter and we have had some 90 degree days so I thought it should of stopped by now.

What is really weird, is I think it only goes so low and then stops. Guess I need to quit filling it thinking it was stretching and see if it does actually drop lower.