Pool Filter Sand Alternatives

FilterGlass close-upEven though they are called “sand” filters, you don’t need to use sand for the filtration media in your sand filter.

If you decide you’d like to make a change you can have product on hand so you are ready to open the pool as soon as the weather cooperates.

If you have had a sand filter for a while, you are most likely already aware that the standard filter media to use is called #20 silica sand. This sand is about .45-.55mm in size and is capable of filtering out debris about 20-40 microns in diameter. As a reference, the diameter of the average human hair is 60-80 microns. Assuming you have good eyesight, particles that are smaller than 30-40 microns are generally no longer visible to the naked eye.

ZeoSand and FilterGlass are two alternatives to standard silica sand, and each of them can generally increase the filtration capacity of your sand filter to less than 5 microns, which is comparable to the filtration capability of a DE filter.

FilterGlassfilter-glass filter sand alternative

FilterGlass is made of finely crushed recycled glass. The glass particles are smooth to the touch, so no worries about adding sharp, jagged glass into your pool filter. Each piece is uniquely shaped (known as amorphous), making it less likely to “channel” as silica sand can over time. FilterGlass has a slightly negative electrical charge which allows it to hold fine, positively charged particles such as iron and manganese.

  • FilterGlass filters out particles as small as 2-5 microns
  • Excellent at removing metals like iron and manganese
  • Removes skin cells, blood cells and 70% of all bacteria
  • Backwash about 75% less, saving water and chemicals
  • Use 20% less FilterGlass than you would silica sand
  • Compatible with all sanitizers, clarifiers and metal removers
  • Does not require backwashing after adding FilterGlass

zeo-sand pool filter sand substituteZeoSand

ZeoSand is made of 100% natural zeolites (minerals found in volcanic rock). The zeolite particles have a 3 dimensional honeycomb structure which gives a cubic foot of ZeoSand about 100 times the surface area as a cubic foot of sand, allowing smaller particles to be trapped.

Because of its lower density and the way that zeolites lay against each other, you’ll use about half as much ZeoSand by weight, than regular filter sand.

  • ZeoSand filters out particles as small as 2-5 microns
  • Traps ammonium ions responsible for chloramine formation
  • Lasts longer than sand and requires 50% less backwashing
  • Use 50% less ZeoSand than you would silica sand
  • Removes and kills bacteria with a molecular sieving process
  • All natural and environmentally friendly

Which Should You Choose?

FilterGlass and ZeoSand will each remove particles under 5 microns in size, so they will both dramatically improve the clarity of your pool water over silica sand.  However, as you can see above there are some difference between the two which may make one a better choice than the other depending on your needs.

If you use well water or find yourself constantly battling metal stains, then perhaps the FilterGlass would be a better choice due to its enhanced ability to remove metals from the water.

If you find that you need to shock frequently, perhaps it’s worth trying the ZeoSand to benefit from its ability to trap chloramine causing ammonia. This will reduce the need to shock the pool, and also reduce red eyes, itchy skin and that “chlorine smell”.

Both of these pool filter sand substitutes require much less backwashing than regular sand, though the FilterGlass will require the least. Less backwashing means less pool water and chemical waste, and more time on your hands!

Standard silica sand costs about $10-15 per 50lb. bag. You generally can obtain this product at a local pool supply or hardware store. Most companies (including In The Swim) do not sell the sand online because the cost to ship the sand is generally just as much, if not more, than the sand itself.

There is no doubt that both the FilterGlass and ZeoSand are both significantly more expensive per 50lb. bag, (current prices are $40-$45 per 50lb bag), but when you consider you will use less of the product (especially in the case of ZeoSand where you zeo-sand-closeupuse half has much), and will likely use much less clarifier and other chemicals, they are still attractive from a cost standpoint.

Are you considering using a filter sand alternative next season? Do you have any questions before you make a decision? If so, leave us a comment below or give us a call at 1-800-288-7946.

Jackie Wolski
InTheSwim Staff Blogger



Pool Filter Sand Alternatives — 17 Comments

  1. Purchasing a new filter and am just learning about ZeoSand and FilterGlass. Given that less of either product is needed. Can I purchase a smaller filter size and achieve the same effect or do I need to but the size I would need if I were using sand?

  2. which is the best or better, #20 sand, HTH sand, zeosand, any others???? I am betting a san filter for my 15 x 48 Intex pool and have not used sand filters before, please advise. thanks

    • Hi, regular filter sand is #20, .45-.55 mm graded sand labeled “Pool Filter Sand”, like HTH sand. ZeoSand is made with zeolites, and is different from silica quartz, with better micron size filtering ability (10 microns) and also the ability to remove ammonia, a primary component of chloramines, or combined chlorine. It needs to be rejuvenated every few years with a cheap filter cleaner, to reactivate some of it’s properties. FilterGlass is another improvement over sand, with sharper edges that lay flat, and also have longer life and better performance. FilterBalls are the newest filter sand alternative, spun polyester, which our own Ryan Dornan has just installed on his pool, so stay tuned for his (honest) reviews, but so far positive with much clearer water and reduced pump run time. So, basically there are 3 alternatives which all promise better performance than filter sand, which can miss particles below 20 microns in size. However, sand is still the cheapest option, and the only option that you may find locally. So there is that advantage. For such a small pool, you would use a smaller sand filter, maybe the Intex sand filter would be a good fit. You may need some adapters to fit the larger hoses to your smaller wall fittings. you also may need to change the filter sand more often than a larger sand filter, which can go up to 10 yrs in some cases, between sand changes. Aboveground sand filters may need new sand every few years, or even every year in some cases, because the sand bed depth is so small.

    • Hi Michael, good question. Filterglass and Zeosand are both fine filter sand substitutes that claim to reduce backwashing frequency of length of time needed, which saves water, which saves salt… so maybe a small advantage there. But not really ‘preferred’ for a salt water pool perhaps.

  3. Ok im new to sand filter system. My problem is the top of the sand in my tank gets kinda hard and dont let the jet blow water back in pool and the skimmer stops flowing as well.i take the big valve off and break up the sand and im good for about 2 hrs then same thing. What do i need to do. Please help.

    • Hi, it could be calcification, from high calcium hardness levels, or other solids (or oils) in the water. I would suggest that you use a sequestering Stain & Scale type of chemical, to keep minerals and metals in solution, and then change the sand, or at least the top 6″ or so of the sand bed. If it continues, dig deeper into the causes. Enzyme treatment may be useful to remove oils, which combine with minerals and dirt, to calcify on the top of the sand bed. If continues without relief, consider FilterGlass or FilterBALLS as an alternative that likely would not clog in such a way.

  4. Can I mix Glass Media & Zeolite together ? (Eg, use 3 layers 1 for course glass, 1 for fine glass and top layer as zeolite ? )

    • Hi, according to Zeolite, you could do this, but they say it’s unnecessary, Zeosand is more effective [than glass]. I could see the two materials mixing however, I don’t think they will stay in perfectly stratified layers, but will mix over time, which may or may not be a problem?

  5. I work at a hot springs resort and we’re constantly battling buildup and channeling in our sand filter. It’s likely a result of the minerals in the water, but being that we have a flow-through system we can’t really balance our water.. We’ve tried sand revitalizers and a layer of pea gravel under the sand as well, but still ended up experiencing channeling within a month.. Do you think filter glass might help at all? I’ve also heard that water softener beads might be a possible media replacement, have you heard anything about that? I realize this is an old post, hopefully it’ll still reach you.

    • Hi Art, Channeling can be a result of very high minerals (as found in natural hot springs), but also can be caused or worsened by high water flow, through the sand bed, or low water flow through the sand bed, too. Perhaps installing a filter bypass valve, to reduce flow rates thru the filter, would help. As for Filterglass, it is probably that the glass has properties that won’t allow it to clump and harden. Sand is also a form of glass, so I don’t know for sure. According to this articles: http://www.poolspanews.com/facilities/maintenance/a-glass-act_o – [glass may not clump and harden as readily as sand, due to a weaker bond formed, allowing minerals to backwash out more easily]- Seems Legit! I’d give it a try. Maybe contact the manufacturer directly? http://www.glassadvantageinc.com/ ask them what they think?

  6. Pingback: Pool Filter Sand | InTheSwim Pool Blog

Leave a Reply

Your email address will not be published. Required fields are marked *