Help with SLAM

[mchimes]

Hello All,

Thank you for this forum. I've learned a lot in reading the posts, but have some questions now. I'll start by saying this pool is old and badly needs to be re-plastered. There are pit marks and rough patches all over the pool that harbor algae (probably 30 altogether). To make matters worse, I let it get very bad (think swamp, tadpoles this year) during the off season every year and have to do massive amounts of work to get it blue and clear. But I have restored it every year (year 9 at this house) with help from the pool store and youtube. That was before I found this site which seems to stress only using chlorine, acid, stabilizer, filtration, elbow grease and time. I ordered the TF-100, but it did not come in time so I am kind of slamming blink right now. But I had to use the 3 day weekend to get started. It actually looks good right now.

Yesterday (see pic below) I added about 1/2 gallon of acid which brought the swamp ph to about 6.8-7.0 (I may have added too much) Then I started slamming with 5 gallons of chlorine with no filter (my old filters maxed out the pressure). Two hours later, I brushed it and added 5 more gallons of chlorine. It was foaming and starting to turn blue and cloudy. I skimmed out the dead tadpoles.

I went to the pool store to buy a new filter and get the water tested. I told them about the advice on this site, but they still pushed algaecides which I bought (but am returning today). Their test measured:
5.0 ppm FC chlorine
5.0 ppm Total chlorine
8.0 pH (which I've read is not accurate during a SLAM)
130 ppm total alkalinity
200 ppm calcium
40 ppm stabilizer

I went home, added two more gallons of chlorine and ran the pump all night with a brand new filter (pressure was 12 with the new filter). This morning, the pressure was 22 and the pool looked blue (see pic below). I cleaned it with a aquacomb thingy and put it back in. The pressure was 12 again. I poured 2 more jigs of chlorine in (20 gallons total by this point) and went to church. When I got home, the pressure was back at 22 and the jets were barely moving. I cleaned it a 2nd time. But the pressure was at 20 as soon as I put it back in. So, I'm wondering if this process is killing the brand new filter. My idea at first was to use floc to drop the solids and vacuum to waste into the yard to save the new filter, but I didn't do that because this floc seems to be a no-no here. I guess at this point, I'm wondering if I should use floc and vacuum or keep cleaning the filter every two hours. Thanks for any tips you can offer.

Mike








15,000 gal. plaster pool
Hayward C1200 filter
Hayward 1HP pump

 

[cowboycasey]

Welcome to TFP

While we usually do not recommend flying blind it looks to be improving..

Your issue is always going to be the filter, You have a 120 sq ft filter on 15000 gallons, I have a 100 sq ft on 700 gallon spa and 320 on 13000 gallon pool

with that said, it can be done but you are going to be cleaning it a lot so this weekend is a good thing.. just keep cleaning it whenever it raises 25% above clean, so clean about 18 psi, 22 is a little high... as more dead stuff gets filtered out the longer the cleaning will be..

no need for floc, algaecides are really not needed unless you are closing, never use ones that have copper/blue in the label

I would stick with 1 gallon bleach/liquid chlorine a day

whenever you get your TF100 post some numbers back in this thread so we can get you going

 

[mchimes]

Awesome- thanks! I did run the hose leaf catcher again and got some more debris out. Looks like I'll be cleaning that filter a LOT.

 

[mchimes]

I got the TF100 test kit in and measured the FC. I tested it 4 times to make sure. The # of drops to clear were : 6, 3, 6, 7 (I'm not sure why its fluctuating), but I figure my FC is 3

FC: 3
CC: 1 (2 drops to clear)
CYA: This was so low that I filled up the observation tube and could still see the black dot in the bottom (even though the pool store said 40) . . . I did it twice to make sure
pH: 6.8

In the last 6 days, I've put in about 25 gallons of pool store chlorine. I don't see signs of algae (except some black deep in rough patches) but it is SUPER cloudy- can barely see the second step. I've cleaned the filter (new) about 6 times and rotated the old one in after a TSP soak. They get above 20 psi within a couple hours. I'll re-read the SLAm page . . . any tips?

Thanks,
Mike

 

[Richard320]

If you floc, all that debris will be concentrated so when you vacuum it up, instead of the filter clogging every ten minutes, it will be after every second pass with the vacuum. You'll end up cleaning it just as often. There's X amount of debris in the water and the filter can only hold so much of it at a time. So the number of cleanings will be the same. The time span will just be shorter if you floc.

Meanwhile, without adequate CYA, a whole lot of the bleach you're dumping in is being lost to the sun.

Get that to 30 and maintain 12 FC and scrub those green patches.

Keep filtering and open a can of

That's Pool Owner Patience.

A sludge pond with tadpoles is going to take more than a week and probably closer to two to get it sparkling again.

 

[mchimes]

Thanks Richard, I am doing an overnight FC loss test. Because I was right at 3 ppm earlier this evening, I added about 1.5 gallons of chlorine and waited 2 hours with no sun. The test came back at 21ppm FC!!!! (2x) Can that be right? Small amounts of chlorine make huge changes. So, I guess I'll check in the morning how much it has dropped. I do have some stabilizer, I think I read you can put it in a sock in the skimmer so it dissolves. As far as scrubbing green patches, I don't know if I have any because I can't even see a foot through the cloudy water. I did a number on it this year! Have learned my lesson!

Thanks for your help

 

[mchimes]

Ok, the FC reading this morning was the same as last night. I also tested TA and it is 170. So my pH is 6.8 and the TA is a bit high. Should I add soda ash?

Report on cleaning methods. I have been using TSP and the aquacomb to clean the filters with decent results, but it still left some of the slimy grey/white film in between the pleats. Last night, I soaked the filter in dish soap (Method brand) and used a regular old telescoping nozzle set to jet stream. It seemed to do a much better job of removing the film.

So, let my FC drop to 12, get some stabilizer in there, get the TA down and the pH up. Whew! getting there.

Thanks for all the help.

 

[Mr Bruce]

pH test is not valid with FC > 10

I am confused, for a SLAM you are supposed to run the pump/filter 24/7. How did you do that and soak the filter overnight?

Could you fill out your signature with your pool details please

 

[mchimes]

I have two filters. Also, I tested the pH when the FC was 3 and it was 6.8. After running all day, I can just make out a shadow of the 3rd step, but we are still VERY cloudy.

 

[mchimes]

Well, I'm going on two weeks and here are the results at yesterday's reading. There is no green algae, but there is some black stuff (algae) deep down in the surface erosion spots in the plaster. The FC loss test has been good for a week and I built a PVC aerator to get the TA down.

FC: 4
CC: .5
TA: 130
pH: 7.4
CYA: 40

After about 20 filter cleanings, the water is approaching clear. You can now see the bottom of the shallow end with a slight haze. You still can't see the main drain in the deep end, but you can make out a slight shadow. I vacuumed up some oak pollen and silt and the texture is chalky and larger grained than I thought. I don't know if that is dead algae or my surface eroding. I'm going to test CA tonight. I hope the kids can swim by Saturday. My main issue now is that even a week old filter clogs after several hours. The hazy stuff is really filling them up.

I'm a lot closer though- thanks for the tips.

 

[cowboycasey]

this is the hardest part "waiting to clear"

So you are no longer at SLAM level, if your pool is still cloudy you did not pass the OCLT, even if you pass 2 of the 3.. it is going to take much longer to get your pool clear with lower FC..

Get that FC back up to SLAM level until your water is crystal clear