Correct order to backwash sand filter and empty that basket? ( + green taking over!)

[Mdragger88]

If You’re referring to the no drain water exchange in section 3.5 of the article linked above. It’s definitely the safest option & is used often to combat high cya &/ high ch. This method can be used to exchange any amount of water you wish.
There are quite a few calculations involved to determine flow rates of draining/filling as well as determining which end to drain from & refill to based on tds & temp differences etc. Be sure to read through to the end & follow the instructions exactly for the best end results.
Speaking of fill water, what is your water source? Municipal or well? Your answer may influence how much water you will be able to exchange/replace at once.

 

[VinylDelight]

I read that page on draining and tested the hose drain, which did work, although with just the passive nature of it it did seem super slow. Am I foolish to try this method? (The chlorine comes tomorrow for shocking.)

The page talks about TDS and temperature. I'm on city water and it's roughly close to the pool water temperature although I did not get a thermometer reading. However, it doesn't talk about algae... which seems like a big factor. Given that I have both an algae plus CYA problem, what is the best way to approach it -- both draining & SLAM order of operations and the issue of hose placement given algae (it is worse in the deep end, and it started there)?

Thank you again.

 

[Mdragger88]

I read that page on draining and tested the hose drain, which did work, although with just the passive nature of it it did seem super slow. Am I foolish to try this method? (The chlorine comes tomorrow for shocking.)

The page talks about TDS and temperature. I'm on city water and it's roughly close to the pool water temperature although I did not get a thermometer reading. However, it doesn't talk about algae... which seems like a big factor. Given that I have both an algae plus CYA problem, what is the best way to approach it -- both draining & SLAM order of operations and the issue of hose placement given algae (it is worse in the deep end, and it started there)?

Thank you again.

The slam process must ensue whether you exchange water or not. It is a waste of chems to begin the slam & then exchange water so that should happen upon completion of the water exchange.
The water exchange is to deal with the high cya not to directly remedy the algae problem even though it may help remove some of the organic matter from your pool. The reduction in cya makes the slam process require less liquid chlorine.
As far as the hose placement goes the algae isn’t a factor in the equation - it’s everywhere lol. It just looks worse in the deep end because there’s more algae filled water depth there.
What hose drain are you speaking of?
You should use a submersible pump & compare it’s gpm output to your water source’s gpm output.

 

[VinylDelight]

The slam process must ensue whether you exchange water or not. It is a waste of chems to begin the slam & then exchange water so that should happen upon completion of the water exchange.
The water exchange is to deal with the high cya not to directly remedy the algae problem even though it may help remove some of the organic matter from your pool. The reduction in cya makes the slam process require less liquid chlorine.
As far as the hose placement goes the algae isn’t a factor in the equation - it’s everywhere lol. It just looks worse in the deep end because there’s more algae filled water depth there.
What hose drain are you speaking of?
You should use a submersible pump & compare it’s gpm output to your water source’s gpm output.

Thank you again, first of all. It seems like we're on the same page here... I know I need to lower CYA at this point, I think part of me just wanted to blast this green pool asap.

The hose I was using is just one of the good rubber craftsman garden hoses according to

The old siphon method​

• "You know, like you used to use when you stole gas from your neighbor's car"...
• Fill a garden hose with water and then put one end of a garden hose in the pool and the other end down hill somewhere.

I'm actually draining it right now and it is certainly slow, but it seems likewise safe as the tradeoff. Maybe it's just letting me feel like I'm doing something until I get a pump or figure things out. There is no major big box store around me so I'm not sure I can just pick up a pump off the shelf as it is.

 

[Mdragger88]

Gotcha - siphon
You should be able to adjust your flow from the supply hose to match the flow from the siphon hose. Just use a 5 gallon bucket & time it.

 

[Mdragger88]

Gotcha - siphon
You should be able to adjust your flow from the supply hose to match the flow from the siphon hose. Just use a 5 gallon bucket & time it.

This will help you see how long you need to do this to exchange “x” gallons of water.

 

[VinylDelight]

So, with the pool filter off and the inlet and outlet hoses going, where should I dip into the pool for a sample of water to test for CYA? I was thinking I should do that tomorrow morning to see if I'm making any headway, or at least reasonable headway; then decide whether or not to go out and get a sump pump.

 

[Mdragger88]

So, with the pool filter off and the inlet and outlet hoses going, where should I dip into the pool for a sample of water to test for CYA? I was thinking I should do that tomorrow morning to see if I'm making any headway, or at least reasonable headway; then decide whether or not to go out and get a sump pump.

Just dipping a sample without mixing the water first may not be a good indicator of your actual cya level.
You need to know how long it will take to exchange “x” gallons of water - so if you want a 50% reduction you need to exchange at least 12,500 gallons. The bucket figuring I mentioned above will help you calculate how long that will take. The flow rates (in & out) must be matched for this to work.
Example- if you are filling & draining at a rate of 1 gallon per minute then it will take 12,500 minutes to complete the exchange. At which point you would stop the process & turn on the pool pump allowing the water to circulate at least overnight but preferably 24hrs before getting a cya sample.

 

[VinylDelight]

So this morning my schedule turned on and the filter ran, but I knew I was doing this drain thing again so it didn't run an hour. How bad is it to run the filter while draining? Obviously it's not a good idea, but I also don't know how bad it is -- after all, water osmosis and stuff will even out the CYA over time, but what that time frame is I actually have no clue.

 

[Mdragger88]

The whole premise behind how the no drain exchange works is that there is very little mixing - running the pump definitely interferes with that.

 

[VinylDelight]

The whole premise behind how the no drain exchange works is that there is very little mixing - running the pump definitely interferes with that.

Yea for sure you are right. I just was wondering how much I guess. I did manage to get the Pentair in "service" mode to pause all that.

So I was wondering, do people that don't use a pool in the winter months just let their pool turn green? Other than running the chems and filters year round, are there other options? I don't think I will be using the pool past October since it is not heated, but this green swamp is certainly not pretty. Perhaps it is because it reflects my failings as a pool boy of course rather than my intentions, lol.

 

[Mdragger88]

Glad to hear you got service mode figured out
Most people who don’t leave their pools open & maintain them year round close/winterize their pools instead.
I close my pool mid to late October in it’s crystal clear state & it is crystal clear upon spring opening at the beginning of April.
I follow this guide

Closing an In Ground Pool

Winterizing a pool is essential for keeping your in-ground pool protected during cold-weather months. This Pool Repair guide will show you how to do it.

www.google.com

 

[Mdragger88]

Even if you don’t plan to close your pool it is a good idea to familiarize yourself with the procedures & know how to winterize it quickly incase of an extended power outage during freezing temps such as we experienced last winter.
TFP’s highest ever number of visitors was during this time due to the large number of people who were panicked & had no idea what to do when unprecedented temps/ice along with rolling power outages made their way across states with generally mild winters.
It definitely pays to be prepared. At my house it was zero degrees & my pool froze solid.
There are tons of threads detailing the aftermath.

Google search results

www.troublefreepool.com

 

[VinylDelight]

So I've seen the ranges often mentioned for target CYA, but it seems like the ranges are large and I don't know enough to know if you want to be low or middle, especially since CYA seems to be a "creeper" type number. (From what I've gathered, you shouldn't need to drain a pool for CYA lowering more than once every 5 years.) When you drain the pool to lower CYA do you want to get the lower number? Bear in mind, I'm not sure how fast my CYA raises as a new pool owner. Another thing I see is direct sunlight means you want higher CYA, and this pool does get a lot of direct sunlight since there is very very little shade.

 

[Newdude]

So I've seen the ranges often mentioned for target CYA, but it seems like the ranges are large and I don't know enough to know if you want to be low or middle

It comes down to location, and point in the season. You will need more protection from the sun than me all year, but both of us need much less than we normally do right now.

Think of the daily loss from the sun as a bell curve. It starts easy, spikes for a while and then falls again. 30 CYA is our start point for liquid chlorine pools. 15 years of lots of members/ hive wisdom has taught us that warm climate folks may need a 40 or even 50 during the peak season to protect their FC from harsh UV burnoff.

30 will be fine for now. We'll help you tweak it next year when the time comes.

^CYA seems to be a "creeper" type number

Only if you add CYA. Tabs are a sure fire way to creep. Follow the TFP recommended chemicals to add and you will actually lose CYA over time and have to replenish a little here and there. We got you now. Things are gonna be great.

When you drain the pool to lower CYA do you want to get the lower number?

It is preferable to overshoot the drain when possible. CYA is real easy to add but real hard to remove. If you have to drain a second round, you lose brand new water with the old. They become increasingly counter productive with each subsequent round.

 

[Mdragger88]

Btw - if you follow TFPC methods you should never need to drain your pool again because of cya.
The Cya is only there because someone added it (via stabilized chlorine products or separate stabilizer) if you only add what your pool needs based on your testing you won’t have a problem.
This is the effect each regular Trichlor puck has on your water

 

[PoolStored]

Btw - if you follow TFPC methods you should never need to drain your pool again because of cya.
The Cya is only there because someone added it (via stabilized chlorine products or separate stabilizer) if you only add what your pool needs based on your testing you won’t have a problem.
This is the effect each regular Trichlor puck has on your water

View attachment 456397

Summarized version of ^^^ this...

If your CYA was 50 at the beginning of the season, after you used 30 chlorine pucks/tablets...you would be back at a CYA level of 90. (1.3ppm/puck * 30 pucks) = addition of 40ppm CYA.

With direct sunlight, and no solar cover, here in Ohio, I can see an FC usage of 2-2.5 in the shoulder months (April/May, Aug/September) and 3.5-4.5 (even 5.5) in June/July. That would likely mean you are using a puck a day, and that after 1-2 months your CYA could be back to 90, starting from 50.

Our recommendation is to use liquid chlorine or a Salt Water Chlorine Generator (SWCG) to add chlorine to your pool daily, and use pucks sparingly when needed (like going on vacation). Liquid chlorine and SWCG do not add CYA, and avoids the yo-yo, pucks, algae, drain, slam, pucks, drain, pucks, algae, drain, slam...you get the idea.

Welcome to TFP!!! THOUSANDS of us that have been on the "learning how a pool works to avoid problems, avoid the pool store and keep the pool open all the time" bandwagon. Keep learning...I guarantee you it becomes like chewing gum, or riding a bike.

 

[VinylDelight]

Wow, this all seems crazy now... how much each puck adds. The prior owner used this pool for about 2 years and they told me they strictly used the pucks, and I wouldn't need to mess with anything else like jugs of chemicals. Were they simply running a ticking time bomb? Honestly they made it sound so easy -- "set the in line chlorine puck thing to 1,5 in the summer and 1 in the winter, shock once a week with a 1lb bag of whatever it is, and do the daily clean of skimmer and weekly robot clean"... But even the "shock" once a week assuming the CYA was only 80 makes me think that 1 pound bag was far far from the recommended shock level. But this is all conflicting with the fact that their pool (until it was mine lol) was crystal clear and beautiful.

 

[wireform]

But this is all conflicting with the fact that their pool (until it was mine lol) was crystal clear and beautiful.

Similar to a very pretty building sitting on a shaky foundation. From above ground it all sits very pretty until the foundation gives way then there's nothing to look at. The pool water looks perfect to a point when the chlorine can't anyore and it all goes down hill. That's why we stress to test and not go by looks.

 

[Newdude]

Eventually they would have been at their wits end on the pool store roller coaster (which costs $175 each lap) and they'd be here too.