Filter sand help

Apr 18, 2014
29
Fayetteville, AR
I've cleared my pond into a grey pool like thing following the excellent advice here. Problem is it hasn't gotten any less grey in a few weeks. FC loss is very low and tied to sunlight, CC is 0, and nothing is visible in the pool at all..
Just grey water. Filter can run 24+ hours without an increase in backpressure but backs up very quickly with addition of small amount of DE following instructions on this site. I inherited the pool when I bought this house in December and the previous owners didn't take care of much (11 bullfrogs, 4 wheelbarrows of leaves, diet, and worms can attest). I opened the filter up today and the sand inside looks to be playsand not graded #20 silica to my untrained eye. Can someone confirm with a pic?
 
FC 10 (slowly dwindling down over the last week with no additions since Sunday) was at 24 at that time
CYA 50
TA 70
CH 100
PH 7.2
CC 0

I maintained shock levels in the pool for nearly two weeks straight at first dropped below the level at night then catching back up the next morning. Went from from green to grey in about six days (early Februrary) and took about 50 gal of bleach total. Once I stopped having to add bleach to keep shock level over night consumption slowed significantly, after a few days CC dropped to current level and has stayed there. Overnight FC loss is within margin of error of tftest kit FC test. I could titrate and dilute the sample but it is repeatedly under 1.
 
It looks like your numbers are all good and have been that good for sometime, correct?

Yet, your water is still not crystal clear? A pic may help if you have one.

If Adding a little DE causes your psi to go up, then it is filtering something out of your pool. Did you stop adding the DE?

If no pic is available, how many steps can you see?
 
Yea, that is pretty representative of my chemistry for the last few weeks.

Adding enough DE to raise backpressure 1PSI (about half a cup, maybe a bit more) cause the pressure to go from 8-9 to 20 in minutes. The filter with just sand will rise to 10 or so but no higher even if on for 24+ hours straight. I have added substantial amounts of DE with no noticeable clarity improvement.

I can clearly see the top step (only two inches deep) and make out the second but that is all.
 
Generally, it is a good idea to run the pump 24/7 when you are clearing your pool. Are you doing that?

Can you tell how much sand is in your filter? should be about 2/3 full or just a bit more.
 
I couldn't at first because I was backwashing every hour or so, but once it got to where I could leave it overnight I did until this past week when I just kind of gave up. It doesn't look 2/3 full, there is 9 inches from the top of standpipe to the top of the sand level then 6 inches to the collection fingers and I don't know where the sand stops below the fingers but there are several inches at least.
 
In the picture of the step, you can see a fine dust that settles on the steps very quickly whether the pump is running or not. I have vacuumed it up countless times and it quickly resettles. I'm sure there is a large quantity of it throughout the pool, but obviously I can't see it. This area received over two feet of rain in less than 14 hours two summers ago and I'm sure that this pool was essentially part of a large lake for a bit until it drained and that is where most of the dirt came in. I was able to remove most of it I believe, when I vacuum very little is caught in the skimmer basket and the filter doesn't seem to clog any faster than normal but again of course I can't see the bottom anywhere and am vacuuming blindly.
 

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I don't know any further history. I bought the house on foreclosure in December , I only lived a few miles away prior so I know the weather history but that is it. I can't imagine it wasn't flooded that day, everything was. The people that lived here prior to us neglected everything, possibly the biggest understatement I have ever made and I was actually shocked when the pump even turned on.
 
That is an entirely different scenario. It sounds like you need to dredge a muddy pool and then worry about your pool chemistry. Chlorine will have no affect on dirt.

I suggest you start running your robot and manually vacuuming (if you can do both)

Of course you will have to backwash a lot.

A pool full of dirt is way different than a pool full of organic material.

It is probably gonna take you a long time and allowing the dirt to settle in between vacs may be helpful. The point I want to make is the SLAM process is not intended for what I now think you have.......you got to get the dirt out first.
 
I think there was a misunderstanding, I already did that. The only dirt in there now is microscopic dust. I got all of the tangible dirt out. I can vacuum the entire pull and not pull up any dirt now, I was explained that the dust on the step and the color on the second step, while.probably related, aren't connected. The second step is simply stained brown probably from years of contact with the dirt which was present.
 
The only dirt in there now is microscopic dust.
Yeah, but SLAM is to eliminate living organics. You must filter the dirt out. Pump 24/7, backwash. brush....all things necessary to get that dust up and into your fiolter where you can backwash it out. Chlorine will not help you.
 
Quick update on my progress. After searching and searching I decided to deep clean my filter, glad I did. Even after a 4 minute backeash so much stuff was coming out with a hose I setup a siphon system to catch the water upon discharge. Basically fresh water in by hose towards bottom of the filter and a short hose out of the top to siphon into a large water catchment tub, an hour later I finally felt that I had reached the point of "clean enough" even though the water coming out of the filter still wasn't quite clear. The sand level in the filter had dropped nearly five inches and while I'm sure I lost a little sand, it wasn't nearly that much as the gunk that settled out in the tub was a several inch think layer in a much larger tank and there was at least an inch think of broken insect shells and such floating also
I refilled the filter to approximately 3/4 full with new sand. The new sand looks smaller than the old sand, but that could be wishful thinking but it is certainly less round. Since the filter had been off for a while at that point, I did a vacuum to waste to attempt to remove any fines which had settled on the bottom and then re-engaged the filter. Within 24 hours there was an immediate and obvious difference, still not clear but substantially less cloudy. I can see approximately 2 foot deep pretty clearly and can make out contrasting colors about 3 foot deep where as before I could only see about 4-6 inches deep and even a bright flashlight lowered into the pool disappeared at about five foot.

I'll let this run another day and then maybe start up the DE routine again and see if I can finally have my oasis.
 
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