Green pool when filter was broken

Feb 28, 2016
56
CYPRUS
Pool has gone green due to a part on the filter breaking, have finally got the part and installed it and filter back in operation. Whilst filter was out of commission I left the pool on recirculation and kept a check on the chemical levels, now that I have put the filter back in service will the water clear up or will I have to slam it? The filter has just been changed with glass as the medium and is virtually unused. Any help much appreciated :) It is the bigger of the 2 pools in my sig....
 
I would not have expected a pool to go green simply because of no filtration. What FC levels were you maintaining and what is your CYA? Were you still routinely brushing the pool?

The pool will clear up, but you'll need to SLAM it if it's green.
 
As suggested, that's what I was getting at in my reply. A pool can be kept sanitized and algae free for weeks without a pool pump. It's just quite a bit more work. Must be brushed every day to maintain circulation. Running a robotic cleaner can help as well.
 
Slamming now in progress, pool has changed colour from a really dark green to a cloudy blue in 24 hours, will continue to slam until it passes all 3 tests for an algae free pool, thank god for this site, it is absolutely brilliant....
 

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Looks like you're getting close! It can take quite a while if the pool is fairly green. At this point, it's up to your filtration to get the water clear but you must maintain FC at SLAM levels during the process. What is meant by "glass" filter. Are you using a sand alternative in the filter? Have you tried adding some diatomaceous earth (DE) to the filter to enhance filtration? Pool School - Add DE to a Sand Filter
 
I have now concluded I have mustard algae, therefore I have raised the FC up to the figure quoted for slamming this type of algae. I have been in the pool today and had both the pool lights out, could not believe how much algae there was behind the shallow end light, both lights and niches are now spotless. Have been under the ladders with a fine tooth comb, so once again they are spotless. The pool is being brushed regularly during this time. I will continue this type of slam for 24 hours and then start to bring the FC down. Do I bring it down to normal levels or down to slam levels?
 
I have now concluded I have mustard algae, therefore I have raised the FC up to the figure quoted for slamming this type of algae. I have been in the pool today and had both the pool lights out, could not believe how much algae there was behind the shallow end light, both lights and niches are now spotless. Have been under the ladders with a fine tooth comb, so once again they are spotless. The pool is being brushed regularly during this time. I will continue this type of slam for 24 hours and then start to bring the FC down. Do I bring it down to normal levels or down to slam levels?
How did you determine that you have mustard algae? Mustard algae is very rare.

Regardless, you do not raise FC to mustard levels until after you complete a standard SLAM.

From the sound of things you are not even close to completing a SLAM (cloudy water, visible algae etc).
http://www.troublefreepool.com/content/148-mustard-algae

I think at this point you are just wasting chlorine raising it to MA level.

- - - Updated - - -

Also, how are you testing, and please post recent results for FC, CC & CYA
 
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Hi, thanks for the reply. I came to this conclusion after I had completed a slam. The pool passed all 3 criteria for the slam, but when I started bringing the FC level down, this algae kept appearing. I did loads of research online and the description For MA was identical to the symptoms in the pool.
 
I now have crystal clear water, the pool has passed all 3 criteria for the slam process. The mustard algae has gone and the pool looks like the other 2 that I look after. Here are my latest readings,
FC 7.1
CC 0
TA 84
PH 7.4
CYA 47
 
Great news!!

Just a note: Sand has been around for millions of years and does not get old or break down. Occasionally, it does need a deep clean, but full replacement is only needed if clogged up and stuck together through the use of pool $tore potions.
 
Hi, thanks for the reply, I did do a deep clean before I refilled the pool, however when I started to use the filtration system again the rubbish I was vaccing was coming straight back into the pool, that is why I opted for a glass medium. The pool builders here quite often do not use the correct sand for pool filtration but will tell you they have. The glass here is very reasonably priced, and since changing over to glass the water is keeping very clean.20160910_111440.jpgHere is the latest photo of the pool now....
 
Pool looks great! I understand about the sand and your reasoning is solid. We had some issues what that last year and early this year. Sand that was labeled pool sand but was not properly sized for pool filter use.
 
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