Pressure up from 15psi to 25psi in an afternoon

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Keeping your questions here is fine ... they may all end up being related [like if your CYA is high, then you FC was likely too low, which would result in algae, which would then clog your filter ;) ]

You should use PoolMath to do your calculations. The Effects of adding chemicals might help here.

If I switch to metric, at the bottom I can input 36g of chlorine gas (I assume this is going to work like the SWG calculations) and with your pool size set at the top, it says it would add 0.6ppm of FC. So for every liter you would add about 0.6ppm of FC.

If I go back to the top and put a FC Now value of 0 and Target value of 0.6ppm, it looks like setting the bleach % to 3.5% would require 1 liter to raise the FC that much.

So, going forward, you could try setting the % to 3.5 and let PoolMath calculate how much to add to reach your desired FC levels. Over time, when you test if you are hitting your target, then you know the pool size and bleach strength is correct. If you consistently miss your target, you may need to adjust the size or the strength.

It is unfortunate that your bleach is so weak.

For the CYA, the lighting plays a huge roll in how well you can see the dot. In the US you can buy a 50ppm standard solution so that you can be sure that you are testing in the correct conditions. Not sure if you can get that there.
 
Wow thanks jblizzle, that's really helpful (and fast too!). So 3ppm of FC = 5L of bleach, Let's hope my CYA reading is much lower tomorrow as that's going to be a lot of bottles. Think I'll keep searching for some higher strength stuff somewhere.

Being the logical type that I am (sometimes) I would have thought an ambient light from close range would have wielded more accurate results than looking at something from a couple of feet away with the the glare of the sun effecting your peripheral vision. I'm sure you're right, there's enough of you guys saying this is the way to do it so I'll try it that way tomorrow and see what reading I get. I'll also do one indoors (being the pedantic type) just to see if there's a difference.

The wife has just told me there had better be a major drop in CYA tomorrow or I'm in the spare bedroom. I've already been told I'm paying the water bill today. :p
 
This mornings CYA test (done 3 times) comes back as 160. That is after draining half to 2/3 of the pool. :mad:

My test strip is now saying my CYA is down to 20 so I think I will need a third opinion on this and will take a sample to be tested. Either way, I'm screwed. If the 160 is wrong and there's something wrong with my CYA tablets then I've just poured 10,000 gallons and quite a few €'s down the drain. If the test is right....what the...! :(

Going back to my sand filter, I contacted Certikin to ask about the spider gasket and whilst I was there asked what I thought was a stupid question but it doesn't hurt to get confirmation. On the side of the filter is says "sand 100kg" and under that it says "Gravel 50kg". As I was using a sand replacement (glass) just assumed I needed to adjust the 100kg down to 80kg as per the bag instructions. Man at Certikin says that it is 100kg PLUS 50Kg so on that basis, I should have 120kg glass (or 127.5kg to 130kg by their 10 to 15% less guidelines). Would less than sufficient sand in the filter make it easier for bits to get through the laterals?

FC came up 0 so have poured 3L of my weak bleach in to give it something to work with until I know where I am at with the CYA

Off to the pool store and DIY store for more glass....
 
Right, so off I went to the pool store armed with the knowledge I've learned from here and with the aid of my 13 year old boy (his Spanish is waaaay better than mine, for reasons I won't bore you with now) proceeded to ask if they did water testing. Only with a test strip came the translated reply. "Not really what I was looking for, I can do that myself, I want a professional test for CYA, can you do that?" (salesgirl looks blankly at me and smiles) I can do a test strip. :roll:

After explaining about my test kit and the different results, she does a test with her strip and sure enough, says my CYA is fine (and so is the chlorine level having put in enough to raise it 3ppm). Her boss then leans into the conversation and between them they ask me what I am using for chlorine. I explain that up until now the chlorine pucks and granules but I will be using......(consults translator to make sure I am saying it right)...Lejio (bleach).

"Lejio!!!" they both say "No, No muy mal" bad for the skin, bad for children, it rots everything, no use lejio. You want these expensive pucks"

"Ok, Forget that then, lubricant! I need some lubricant for my multiport handle" (demonstrates taking it apart, smearing lubricant and putting it back together on shop model filter).

"Vaseline?"

"No, Lubricant"

"yes, vaseline"

"No, Lubricant, vaseline bad, lubricant good"

(looks at me blankly and then says) "We don't have vaseline" Which cause me to LOL (I make some polite noises and then leave)

DIY store, 3 large pallets of bags, one for sand, one for salt and one for glass media....containing one very sorry looking bag of glass....of course I need two and of course there aren't any more in stock until next week. :cry:

I'll wait before adding the extra bag of glass for someone here to tell me whether Mr Certikin is correct and that my 25" filter really should have 120kg of glass in it and not 80kg (or 150kg of sand and not 100kg, I'm sure you guys know the correct volumes) and then try and find another pool store that can do a proper test for CYA.

Pool looks great though and if my wife asks, everything is fiiiiiiine ;)
 
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Searching the forum it would seem that Mr Certikin is correct and I need to add more glass to the filter. I can't find any info on my filter about freeboard so I'll just go with 2 more 20kg bags and measure how much of a gap that leaves me. I know not many of you here use glass but is there any benefit in adding different size glass to the 0.6mm - 1.2mm that I have in there? I've read that with glass you don't need to have the pea gravel/sand combination but I've seen one or two people that have opted for two sizes of glass (but that was 5 years ago). Is there a consensus of opinion on what grade glass would be best? With the last bag that I need to buy, would going for a finer grade (to filter out more) or a coarser grade (to sink to the bottom and do what pea gravel does) give better results?

My wife was sceptical of my story about the pool guys and she snuck off to google "bleach for swimming pools". 30 minutes later and she's now onboard and helping me look for suppliers of stronger bleach :goodjob:
 
So I'm about to put two more bags of glass in the filter and I see more than the usual small bubble of air in the pump basket viewer. There's a good half an inch churning over but the water levels are fine and the lid is nice and tight so there's no obvious reason for air to be getting in. When I stop the filter I hear a gurgling from the filter and I can see a large bubble in the clear glass dome which is being agitated by the gurgling water. Because I was about to open the filter I released the pressure valve on the top and it starts letting out air and after 20 seconds I start to close the valves and when I close of the return valve, the air stops coming out the filter. I open and close it again just to make sure it is the valve cutting off the supply and sure enough it is. So if air is coming out the release valve, water must be going in and it's going in from the return pipe. Should it be doing that?

I don't fancy opening a pressurised filter so I guess I should continue letting the air out but just wanted to check with you guys if this is normal.

Thanks again

**Edit**

I just stopped the pump and when I did, all the water in the pump basket got sucked back into the filter. All the valves were open but there was only a slow trickle of water into the almost empty basket and eventually even that stopped. A small amount of air came out of the filter release valve but only when I started loosening the pump basket lid did that let the air out and allow the water from the valves to fill the basket. Once filled, I started the pump again but it was struggling to pull water in and the pump basket was only half full for 30 seconds and then slowly started to fill up but not fully. It was back to where I first saw it with half an inch of air at the top churning away but not getting smaller. Is this ringing any bells for anyone? What has caused this sudden air lock and what causes the water in the pump basket to be sucked into the sand filter (leaving the basket almost empty) when the pump is turned off?

Not seen this before so any clues as to what could be causing it would be much appreciated.
 

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jblizzle said:
You are hearing air sucked into the filter when you open the air release valve. It is not coming out with the pump off.
Click to expand...

Ahhhh, right, so I guess I don't need to open the pressure valve before taking the lid off. Thanks for that jb, that's put my mind at rest. I'll put the extra glass in tomorrow and also take another FC reading for the OCLT. My test results are still all over the shop but I don't think there is much I can do about it as I can't justify emptying the whole pool as that's what it will take. Latest readings:

PH - 7.3
FC - 3
CC - 0.8
CYA - 160
CH - 560
TA - 150

I made a mistake with my chlorine readings last time, I multiplied by 0.5 instead of 0.2 so they should have read FC 1.2 & CC - 0.8. With my weak bleach (the best I can find is 40g per litre so only slightly up on the 37g I've been using). I'd need so many bottles (haven't actually calculated it but I'm guessing it's a ridiculous number) to lose the CC that I'll probably just keep on with the '1 bottle a day' regime and see if the CYA, CH and TA come down by themselves with regular backwashing. Not the best plan but I can't see too many other options.

I'll raise the PH a little as I've never had it higher than 7.4 so will see if that helps things along. Still no joy in finding anyone who can test water, I'm beginning to wonder how the average guy in the street here manages to keep their pools green free.

Pool still looks great though and beautifully clear today (partly helped by my Ebay slimebags), despite the big numbers.
 
Your pool has a very high CH given that you just drained and refilled half of it. It may be that you had a CH over 1,000 and a CYA over 300 before you did the drain. I'm going to suggest you test the CH of your fill water, if it turns out to be low, say around 200, that would confirm you had real high numbers to begin with.

If this is the case you'll have to do another drain and refill to get that CYA number down. You'll need to drain more than 50% to get the CYA down to 30. I strongly suggest not discussing this with the wife ;), with any luck both both refills will appear on the same water bill. Ignorance is bliss. :cool:

Good luck with the pool!!! It's a lot to learn, but give it a couple of months and it'll all be old hat. Go have a pie and a pint when it gets to be too much, your pool will still be there next day. :p
 
Thanks prs, that's a good idea about testing the fill water.

The CH was 880 and the CYA was 160 (120 once but 160 4 times) before the drain and I was very restrained in letting as much drain as possible. The urge to close the tap and start refilling was very strong. The clock was ticking and I wanted to say to the wife that I had just started the refill when she got home :p. Unfortunately, it took almost 24 hours to refill so the only chance of me being able to drain it again (by 75 to 80% next time) is when she will be away, which is not any time soon.

My hope that the CYA reading is wrong is fading by the day because my overnight FC reading for the OCLT is 0 (clear tube)..... so 3ppm disappeared overnight. :grrrr: THE CYA is so high that slamming is almost pointless because I could never maintain the level of FC to keep the CC at 0. I poured four 5L bottles of 3% weak bleach in yesterday afternoon and whilst it was still there at 8pm, it vanished overnight.

I've only found one store selling anything other than weak bleach and it's called Clorogene. It has 150/180mg chlorine per litre but bizarrely lists the bottle as 12kg so not entirely sure how many litres that would be. At €17.90 (nearly $20) it's not cheap but would it really help/make a difference? I'm a little bit stuck as to what to do now. I can't really be dumping 5 x 5L bottles of 3% bleach (at a cost of €6) in a day only to see it evaporate overnight.

I've just added the extra glass to the filter and did a thorough 5 minute backwash and 1 minute rinse ("had to be done darling, new glass needs a 'very' good cleaning so it can't be helped"....got away with that one!) so I'll sit with my pie and a pint :goodjob: and contemplate my next move.

*edit* "d a m n" is a bad word in the US? It's extremely mild in the UK, just saying like.
 
I just read all your posts... Maybe this will help.

If you "backwash" every day for 15 minutes your CYA would go down, not fast but it would happen...

I just thought of something that may help you out ALOT... Have you thought about going to a salt water generator? A SWG needs CYA between 60 to 80 and SWGs produce chlorine from the salt that you add to your pool.

http://www.troublefreepool.com/content/127-salt-water-chlorine-generators-swg
http://www.troublefreepool.com/content/138-water-balance-for-swg-saltwater-chlorine-generator

They are expensive up front and that's the bad part, the good part you would not have to track down bleach..

You would need at least a 45,000 or 60,000 gallon SWG, they go for around 900 dollars us, I am not sure where you could get one there. here is the one I bought for my pool.. http://www.discountsaltpool.com/CircuPool-SJ-45-Chlorine-Generator.php

the only 1 I found in www.ebay.es was this one, maybe you will have better luck locally..

http://www.ebay.es/itm/Rebuilt-Hayw...715?pt=LH_DefaultDomain_0&hash=item3ce62a8f9b

Hope this helps
 
It does seem that you are caught between a rock and a hard place. :cry:

You have an algae problem that is eating up your FC and blinding off your filter, and the only way to get rid of it is to drain the pool to get your CYA down so that your slam FC level is brought down to something reasonable. Alternatively you can wait for the pool to go cloudy and then go to the pool store and ask them what to do about it. They will try to sell you some very expensive shock chemicals that might work for a month or so and then the problem will come back.

Maybe you can go to the pool store now and find out the cost of the shock chemicals, and then sit down with your better half and go over the costs of each alternative. If you can put together a good enough story maybe she'll agree to another drain. :handshake: If not you'll just have to wait until the pool turns green. :lol:

In the USA laundry bleach is available at every supermarket. It's all 8.25% and at my local Target a 3.6 liter jug costs about $3. Maybe you can check out the Spanish equivalent to Asda or Aldi and see what they have?

Do you have a thick white line on the tile around your pool at the water line? I ask this because with your high CH any time spent at high pH would have produced calcium scaling. If this is the case, it might be another point in favor of a drain because you could get rid of the scale when the water level is down. If you haven't yet figured out how to input your test results into PoolMath and obtain your CSI (calcium saturation index) now would be a good tme to do so.

"D a m n It" is not a very common term in the USA but I don't think it's regarded as being particularly bad. I use it all the time, but then I was born and raised in Lancashire so I get some leeway over here. :eek:
 
I tested the fill water (as per prs suggestion) and the CH was 380 (19 drops at x20). That seems a little high (or hard) and not much I can do about it. I also did a CYA test on my fill water and sure enough, it was clear (and then another pool test @160).

The Pool calculator has my CSI at 0.08 now and -0.04 as target, that doesn't look too bad. Quite how my high readings are giving me a good CSI is another matter.

The SWG suggestion is a good one and I'll bear it in mind for the future. Money's too tight for that kind of expense this year but with the lack of high % bleach here, it's a good solution.

The pool pucks and chlorine granules will be confined to the shed so I'll not be going near the pool store for any chemicals. I'll continue with bottles of weak bleach and the odd sneaky 1000 gallon drain when the wife's not looking. I know this is not the most productive way to do it as I'll be losing some of the fresh water with every drain but if I stick at it, in a few months there should be a difference.

I think I may have stumbled on something that is probably my algae problem. You know how you can be looking at something full in the face and not see it? Well, today I had the hose pipe in the pool and it was merrily snaking about when it faced up against the side of the pool and 'water blasted' it. I suddenly saw there were little bits hanging of the side and some had floated to the floor. My wife has now told me that the pool is 20 years old and it has never been drained or thoroughly cleaned and what I was looking at was a build up of 'something' between the tiles on top of the grout. It's grey and spongy and moss like so I spent the next two hours with the hose pipe strapped to a pole water blasting the sides and floor. How did I not see it before? I just thought the grout was a dark grey colour....ewwwwwwww!!

I'm only 10% done so I've got some work to do get the rest out and if I'm honest, that's probably me done for a couple of months, at least until the CYA starts to come down.

Thanks for all your advice guys and gals. I'll be back when I have an update.

:wave:
 
Desiato said:
My wife has now told me that the pool is 20 years old and it has never been drained or thoroughly cleaned and what I was looking at was a build up of 'something' between the tiles on top of the grout. It's grey and spongy and moss like so I spent the next two hours with the hose pipe strapped to a pole water blasting the sides and floor. How did I not see it before? I just thought the grout was a dark grey colour....ewwwwwwww!!

I'm only 10% done so I've got some work to do get the rest out and if I'm honest, that's probably me done for a couple of months, at least until the CYA starts to come down.

Thanks for all your advice guys and gals. I'll be back when I have an update.

:wave:
Click to expand...
Isn't your wife admitting it's time for the pool to be drained and thoroughly cleaned?
 

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