Recycled glass vs silicate sand

couzin2000

Member
Mar 14, 2016
16
Ste-Therese, QC, Canada
Pool Size
80000
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Hayward Turbo Cell (T-CELL-5)
Here's the situation. I just purchased:
-Pentair Intelliflo pump
-Hayward low-salt chlorinator
-Hayward sand filter

In order to keep the flow nice and ensure my chlorinator works proper, there's gotta be a certain debit. When my pump works at 1800rpm (info which I got on this forum) I get 1800ppm chlorine levels. Sounds good so far for a 60,000l pool.

However, no matter what I put in the pool, product after product, I've manage to get water chemistry in PERFECT balance according to testing at 3 different stores.

So why is my water still green?

I think it's because my pool needs a good vacuuming, but there always seems to be some sort particules suspended in the water that I can't get rid of. As a result the water is cloudy on its best day.

I spoke about this to the store specialist. She tells me that the pressure in my filter could be too low and not filtering properly. I checked. At 3000rpm, water pressure is 20millibar (is it PSI?). The filter sticker states it needs 10 to operate.
At 1800rpm, the filter is at 7-8millibar/psi.

Could it be that the recycled glass inside the filter cannot be compressed together the way silicate sand can be? Is this why pressure is so low at lower rpms and why my water always seems to keep some particulate matter suspended?

Should I be swapping out glass for sand in my filter?
 
I am not sure I have seen a post with more gibberish in it than this. Water clarity is all about water chemistry.

You are being COMPLETELY pool stored. That will never stop unless you decide to make a huge change in your pool management and I mean huge.

You must start to learn water chemistry. read "The ABC's of Pool Water Chemistry" up in Pool School.

Your pool will never be clean unless you gain an understanding of pool chemistry.

Next, you desperately need to stay out of the pool store and start to do your own testing. Everything we do begins and end with accurate testing and the pool stores are incapable of providing that.

I'll let you digest that information above for a while. Post back if you feel you are ready to commit to learning what we teach and willing to start doing your own testing. Without those two, we will be of no help.
 
Welcome to TFP :)

Your pool is green from 1 of 2 things

algae or metals, did the pool store check for metals? if none you have algae, you need a Taylor K-2006C or the smaller K-2006, I would recommend the bigger one for a green pool..

They are expensive up north but after you spend some time on the site you will see the pool store is not there to help you, they are there to sell you everything under the sun and keep you coming back..

You filled out your Signature, great job.. so you have a SWG, we also need to know what your CYA is as that is an important part of keeping your pool clear..

we can help but you need to be able to do your own tests 2 to 6 times a day until your pool is nice and sparkly :)
 
I am not sure I have seen a post with more gibberish in it than this. Water clarity is all about water chemistry.

You are being COMPLETELY pool stored. That will never stop unless you decide to make a huge change in your pool management and I mean huge.

You must start to learn water chemistry. read "The ABC's of Pool Water Chemistry" up in Pool School.

Your pool will never be clean unless you gain an understanding of pool chemistry.

Next, you desperately need to stay out of the pool store and start to do your own testing. Everything we do begins and end with accurate testing and the pool stores are incapable of providing that.

I'll let you digest that information above for a while. Post back if you feel you are ready to commit to learning what we teach and willing to start doing your own testing. Without those two, we will be of no help.
Well first of all, I really appreciate the way you welcome other users. If you do it this way everytime, telling people what they write down is "gibberish", you'll soon end up in this forum on your own. So thanks for that.

THAT BEING SAID, I did mention that I have done 3 different places to test the water, and I am waiting for an order of a Taylor k-2006 from Amazon.ca. I am aware stores have their own levels of "what is acceptable in the pool", so the tests differ and answers differ in function of what they need to sell you. And while I did read the "The ABC's of Pool Water Chemistry" many times already, I do still see particulate matter floating in the pool water. I get that the water is not clean, but I don't own a filter for nothing. It does do its own job, and if you believe that strict chemistry is the only way to change water color, then by all means, keep welcoming people like this and refer to the first 2 sentences in this reply. No offense.

The subject of this thread is to verify whether or not I should be using recycled glass or silicate sand - which is best for me and which will ensure I can keep my pressure at acceptable filtering levels while lowering the rpms on my variable-speed pump. I did post this in the right section of the forum.

(Trust me, I will deal with the pool chemistry as I have been doing already, and I know my pool needs some cleaning. So, if you're gonna answer my question, please do so... otherwise please let someone else be rude to me.)
 
Glass filter media is not the problem....glass works just as well as sand and I've used both, I had glass at my last house/pool installed by previous owner.

it might actually have an advantage over sand, it tends not to "channel." But that's a debate for another time.
 
I think Dave's gibberish comment deals with pool stores saying the water is perfect. How is the balance perfect if there is algae?

So, to the original question - Yup, glass will work just as well as sand in filtering. The only thing glass media does a little better is fill the bank account of the person selling it to you. But, as Dave said algae is due to chemistry issues not filtering. You can have the best filter and vacuum three times a day. If the chemistry is off you will have algae.

You have a K-2006 on order so you will be able to SLAM the pool. But, the K-2006 is woefully short of the FAS-DPD powder and Reagan so you should order more now.

Or, you can follow the recommendations of the pool stores who say you water is perfect. I would recomend the SLAM Process
 
Glass filter media is not the problem....glass works just as well as sand and I've used both, I had glass at my last house/pool installed by previous owner.

it might actually have an advantage over sand, it tends not to "channel." But that's a debate for another time.
Awesome. I have been doing some reading on the forum and the most I see is one dude apparently had a problem with it in Africa. From what I understand it is less compressible than silicate sand, so pressure at low speeds could be too low for the filter to do its work properly. I'll have to work out a proper speed so my water pressure doesn't drop below 10-12. Thanks.
 
I think Dave's gibberish comment deals with pool stores saying the water is perfect. How is the balance perfect if there is algae?

So, to the original question - Yup, glass will work just as well as sand in filtering. The only thing glass media does a little better is fill the bank account of the person selling it to you. But, as Dave said algae is due to chemistry issues not filtering. You can have the best filter and vacuum three times a day. If the chemistry is off you will have algae.

You have a K-2006 on order so you will be able to SLAM the pool. But, the K-2006 is woefully short of the FAS-DPD powder and Reagan so you should order more now.

Or, you can follow the recommendations of the pool stores who say you water is perfect. I would recomend the SLAM Process
I agree. I did make one LOUSY mistake when adding the proper quantities of FC when starting up the pool (which was late in the year, I'll concede): the person at the store explained half-assedly that when diluting my FC in pool water (in a separate bucket), "whatever is leftover isn't good and I should throw it out". So imagine the amount of FC I didn't get diluted and threw out. That should have gone into the pool, along with the calcium leftover, which would have probably raised my TA and pH... but not by much. So the FC is not in the pool. Which means I have to add some, hence duraleigh's comment. and this IS something I must tackle, but I need to address one thing at a time.

I probably will SLAM the pool, but there is much to do, and I am not at the pool day in day out, so this becomes a problem to startup... especially with my 4-year old asking "whenisthepoolgonnabeready? whenisthepoolgonnabeready? whenisthepoolgonnabeready?" :compress:

Thanks for the help!
 
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I used that glass media with a little DE, I liked it but I replaced my filter with a larger one and switched back to sand. With DE you can run at slower speeds and get more back pressure.
 
I used that glass media with a little DE, I liked it but I replaced my filter with a larger one and switched back to sand. With DE you can run at slower speeds and get more back pressure.
I don't necessarily want to add something as unstable as DE in the system at this point. Still trying to get a hold of the chemistry in the water... to me, DE is something in the "Expert level" bracket. I wouldn't try it right now.

Plus, as I was thinking about the glass media, I realized that glass can work better than sand at higher rpms (like 3000rpm), for me the pressure inside the filter is only good (above 10) while running fast. No point in backwashing for now, either.
When my rpms drop at 1800 (to save energy), pressure drops below 10 and nothing gets filtered properly.
As I was thinking, the glass media can do a better job at the beginning of its life cycle. But as the years go by, water and particle matter runs through and polishes the glass edges. So the glass's efficiency at filtering starts dropping on day 1, so even though you can use it, I would recommend using that in small filters. In a pool like mine, you need the bigger filter, and you need to run a large pump, in order to save money you're going to have to lower the water flow, so sand is really the best choice, as far as my understanding goes.

That said, I will be changeing the glass media to sand, but that as soon as pool chemistry is back to normal.
Currently SLAMming the pool. FC levels at 4.0, gonna keep them in that area for a while. When that's done, I'll change to sand.

As soon as I have a Shop-Vac :p
 

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Some people commonly add 1/2 cup of DE to help polish the water without any issues. But as others said (and you are focused on), Figuring out chem levels and why alge is growing is priority #1. It will be interesting to see your CYA levels as these can become elevated over time reducing the effectiveness of chlorine and requiring high FC levels to prevent alge. Especially if you have been using tablets for sanitation. If your test comes out near or over 100, retest and do a 50/50 dilution with freshwater and multiply results by 2. Pool store indicated my CYA was 112 on several occasions. Using the dilution method ( had to gor 4:1), it was actually 320! Was having problems with alge 8ppm FC and couldnt figure out why. Drained and refilled and pool stays crystal clear now at 4ppm with 45ppm CYA.
 
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