SLAM-A-JAMA time?!

[Gman529]

Hey all you pool cat and kittens!

After many battles with my pool I have turned to the internet and I feel grateful to have now found this community as I hope my time here turns me from an ignorant pool-boy to well educated pool-man!

To get everyone up to date I have an in-ground open-air pool. I bought my house a few years ago and knew nothing about pools then and still know very little now.. but I've been digging into the resources here and trying to learn! My first step was buying the K-2006 test kit which was delivered today and here are the following results from my tests:

pH: 7.4​

FC (1 drop = 0.5 ppm): 34 drops to get to clear = 17 ppm.​

CC (Don't know if this really worked): 5 drops of R-0003 did not change color at first. 30 to 45 sec later color changed to a slight purple color and it took 5 drops to get back to clear = 2.5 ppm​

TA: 70 ppm​

CH (Don't think this one worked at all): I couldn't tell when it went from red to blue. More like red to clear/very slight tint of blue. Between 30 and 40 drops = 300-400 ppm​

CYA (Why didn't I just do this one first so I could have saved the reagents from all the other tests?): 100+ ppm. The test kit's first bar is 100 ppm and I didn't even make it halfway to that mark.​

From what I've read on this site so far, based on my CYA test result, I should drain at least half my pool and fill it with tap water. The thing is... I have no clue how to do that! I have attached a picture of my pump and filter system and I do not believe I have a way to drain water to waste. So any ideas on how to tackle this issue would be appreciated!

On how my CYA levels got so high? I've been battling a gnarly algae problem that just wont go away and in my ignorant wisdom I thought lets put the 7 remaining chlorine pucks I have into the pool at once to try and really shock the system!, which was clearly a mistake. I have scrubbed the floor and walls with my brush and when the pump is running it does a good job to clear up the pool a bit, but as soon as the pump is off overnight the floor goes back to a layer of algae. I ran my pump for a couple of days and cleaned the filter during but it didn't matter, the algae would come right back as soon as the pump was off for a few hours.

Anyways, thanks for coming to my TED Talk. I hope to learn how to defeat my pool monster and keep the pool in good shape going forward and I plan to document my process here as I know I will have questions along the way.

 

[kellyfair]

Lol, got a kick out of your greeting! So, I’m inviting @mknauss to come in and talk about how best to drain water. Good job on grabbing test kit and running your numbers, by the way. That’s a great head start. And your instinct is correct on the chlorine test. If you let it sit, it will go pink again, so just add the number of drops to turn it clear and use that number in your calculation.

Your instincts are also correct regarding the tabs contributing to your CYA.

I feel like with your good head start, you will conquer your green beast very quickly!

 

[kellyfair]

And by the way, hi, neighbor!

 

[an1vrsy]

Welcome to TFP! Find a good source for liquid chlorine In your area. You are going to need quite a bit. I don’t know Florida very well, but Walmart sells liquid chlorine.

 

[mknauss]

Well, in Orlando Florida, I would suspect it is not a good idea to drain a gunite pool. You have shallow water tables there I believe.

So, you will need to do the exchange process. Read about it in Draining - Further Reading
The temperature of your fill water and pool water will help determine the configuration for the exchange.

You will need to exchange the entire volume with that CYA test result.

 

[kellyfair]

Pinch-a-Penny has the refillable jugs for liquid chlorine, very reasonable.

 

[Gman529]

@kellyfair Yes I have a local PaP that I go to for my liquid chlorine. When I first got the house I let them sell me a bunch of products (quite expensive I might add) after giving them a pool water sample to test. Now I primarily only get the chlorine refills there.

@mknauss So I shouldn't do a dump of half the water? I'll look into that exchange process you linked.

 

[mknauss]

So I shouldn't do a dump of half the water?

There is risk in draining. With what you reported from your CYA test, you need to essentially drain the entire volume. If you decide it is safe to do partial drains, it will take several.

 

[Gman529]

Hello Friends! I am back after accumulating the tools to perform a water exchange. I'm not sure if I should be updating this post or creating a new one but here I am and I now have a new problem to tackle!

I have a sump pump that will pump out of my pool at around 1200 gal/hr. And my input from my spigot is 300gal/hr. (I measured and timed these two using 5 gallon buckets and a stop watch)

The pump does not have any speed control settings so its either on or off. If my plan is to do a water exchange where I am pumping out from the shallow end and filling up into the bottom of the deep end at the same time, how can I do this safely without pumping out to much water?

 

[mknauss]

Two hoses? That is a really slow rate out of your hose.
You can pump out and fill for a few hours then turn off the pump to catch up. Or you can restrict the hose from the pump to match the fill rate.

 

[Gman529]

So with 2 hoses I calculated 420 gal/hr fill rate. This was from my two spigots and 100' garden hoses attached to each. According to what I just googled the flow rate through a garden hose is apparently effected by the length of hose so it doesn't help that I only have 2 100' hoses. However that goes against what I learned in school that flow rate is dependent on velocity of the water and the cross sectional area of the conduit.

 

[mknauss]

Length of the hose effects flow a lot.

Like I said, two choices. Run the pump on and then off to keep up or restrict the hose from the pump.

 

[CrystalRiver]

Length of hose matters because the velocity is determined by pressure. More length = more friction = more pressure loss = lower velocity.

 

[amwillg]

Late reply. Hope exchange and SLAM went well. That filter seems small for pool size? Does it need cleaned super often?

Need result pics!!!

For reference:
Resistance = (8*length*viscosity)/(Pi*radius^4)
So...
Double length = double resistance
Radius is exponential difference, so pick the largest diameter hose you can get if you have a long run to help offset resistance

 

[Gman529]

Hello everyone, I'm back to give an update. My pool is still green but really I haven't tried tackling the green aspect of my problem yet. For full disclosure I have not been able to give this my full attention as I've been dealing with multiple other things, the most tragic being a family member has been in the hospital for last 12 days with COVID and its seems like there is nothing doctors can do further to help treat their condition. We are at the stage of wait and pray and the past 2 days have not shown any signs of improvement so the outlook seems very grim.

Pool related I was able to work on the water exchange. As of now I have exchanged ~5' of water. Its been a slow process because the pump will take out 6" in less than 2 hours and it takes at least 4 hours to refill back up with clean water. The deep end is a little over 6' deep so I'd say probably 70-80% has been exchanged. My method was to put the pump in a 5 gallon bucket and set the bucket on my lowest step of the shallow end. The thought there was this would try and raise the level of the water being pumped out as the water would be sucked from the top elevation of the submerged bucket while I have been filling from the floor of the deep end using two garden hoses. Obviously this isn't an exact science and I understand there is some mixture happening. I reran a CYA test and I am in-between 30 and 40 which is a huge improvement from the over 100 result I started with. My plan is to exchange another 2' and run the CYA test once more before going forward with the rest of the SLAM process. Another pool related hiccup I had was just before I started the water exchange I noticed my pool pump was leaking out of the bottom of the band clamp. I ended up taking my pump apart, cleaning it up and replacing all gaskets and seals. When I put it back together there were no leaks so I was pretty happy with my effort there. I did run the pump for half a day before I did the last CYA test because I wanted to make sure I was getting an accurate reading.

@amwillg I don't find the filter needs to be cleaned that often. I go by the PSI gage and when its 10 higher I will give it a thorough wash. Maybe every couple of months I need to do that.

(edited for typos)

 

[kellyfair]

Hi, Gman. I’m so sorry to hear about your relative. Best wishes for recovery and for your family.

 

[Gman529]

Thank you @kellyfair


Well today I finally began the SLAM process to defeat my green monster! My tests this morning indicated a reading I assume to be slightly lower than 30 CYA (My kit stops at 30) and I now see I should have ended my water exchange when I was getting a result between 30-40 CYA but such is life and here we are. My pH was 8.0 so I went to my local pool store and got a jug of MA. I also stopped by wally world and they had 10% bleach that was only 4 weeks old so I grabbed 12 1-gallon jugs to be prepared for this battle.

This afternoon I followed the acid demand tables in my book and added the MA to get the pH down to 7.2. After letting the water circulate for an hour I did the other tests and results are as follows:

FC = 0.5 ppm
CC = 0.5 ppm
TA = 70 ppm
CH = 100 ppm

I entered this into the pool math calculator (see below) and then followed its instructions to add 1.4 jugs. The pump is running and I will test my levels again tomorrow morning.

Is my goal from here on out just to focus on the FC level? Keeping it at ~12 until the algae is gone? I know I need to scrub the pool walls and floor with my brush everyday and keep an eye on the filter's psi gage to clean out the cartridge when it goes up. I don't have a true pool vacuum, just my Polaris 360 which imo is more of a leaf and large debris collector. I wasn't planning on running it during this process because I don't love the idea of it being in such a high levels of chlorine for as long as this process may take. Any advice for this pool newbie?

 

[kellyfair]

Yes, you want to focus on testing FC and re-dosing to SLAM level for your CYA as often as you can. By the way, the Pool Math app for smart phone is much more user friendly!

 

[Gman529]

This morning's result:

FC: 6.5 ppm
CC: 1.0 ppm

Added recommended amount of bleach to get to 12 FC. Will test again at lunch time.

 

[Gman529]

Day 2 - Lunch time update:

FC: 6.5ppm
CC: 0.0ppm

I washed my cartridge filter because the gauge had gone up a few PSI. Added recommended amount of bleach to get to 12 FC. After 30 min I retested FC and it came out as 13 FC. I think my pool may be slightly smaller than the 12000 gal I've been estimating.