{"id":4178,"date":"2026-06-19T13:03:43","date_gmt":"2026-06-19T13:03:43","guid":{"rendered":"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/"},"modified":"2026-06-19T13:04:31","modified_gmt":"2026-06-19T13:04:31","slug":"pool-filter-leaking-from-bottom","status":"publish","type":"post","link":"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/","title":{"rendered":"Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide"},"content":{"rendered":"<p><strong>Quick Answer:<\/strong> A pool filter leaking from the bottom usually means one of four things \u2014 a cracked filter tank, a worn drain plug O-ring, a failed belly band clamp, or loose plumbing connections. The good news? Three of these fixes cost under $20 and take less than an hour. The bad news? A cracked tank means replacement time.<\/p>\n<p><!-- PCC AI SUMMARY START --><\/p>\n<section class=\"pcc-answer-card\" data-ai-summary=\"true\">\n<h2>Quick answer<\/h2>\n<p>Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide: Quick Answer: A pool filter leaking from the bottom usually means one of four things \u2014 a cracked filter tank, a worn drain plug O-ring, a failed belly band clamp, or loose plumbing connections. The good news? Three of.<\/p>\n<\/section>\n<p><!-- PCC AI SUMMARY END --><\/p>\n<p>Discovering your pool filter leaking from bottom connections is frustrating. You walk out to check on your pool, and there&#8217;s a puddle spreading across the concrete. Maybe it&#8217;s a small drip. Maybe it&#8217;s a steady stream soaking everything within three feet. Either way, you need answers \u2014 and you need them now.<\/p>\n<p>I&#8217;ve diagnosed hundreds of these leaks over the years, and here&#8217;s what I&#8217;ve learned: 90% of bottom filter leaks fall into a handful of categories. Once you identify which one you&#8217;re dealing with, the fix becomes straightforward. Let&#8217;s figure out exactly what&#8217;s causing your leak and get it stopped.<\/p>\n<hr>\n<h2>Step-by-Step Diagnosis: Finding Your Leak Source<\/h2>\n<p>Before you can fix anything, you need to pinpoint where the water&#8217;s actually coming from. Water travels, so that puddle at the bottom doesn&#8217;t always mean the leak started there.<\/p>\n<h3>Step 1: Turn Off Your Pump and Observe<\/h3>\n<p>Kill the power to your pump completely. Not just the timer \u2014 flip the breaker. Now watch the filter for 5-10 minutes. Does water keep dripping? A leak that continues when the pump is off tells you it&#8217;s gravity-related (drain plug, tank crack below water line). A leak that stops immediately points to pressure-related issues (clamp seals, plumbing fittings).<\/p>\n<h3>Step 2: Dry Everything and Watch<\/h3>\n<p>Grab some old towels and wipe down the entire filter housing, every fitting, and the base. Get it bone dry. Now turn the pump back on and watch closely for 2-3 minutes. The first spot to get wet reveals your leak source.<\/p>\n<h3>Step 3: Check These Four Common Culprits<\/h3>\n<p>Run through this checklist in order:<\/p>\n<p><strong>1. Drain Plug Area<\/strong> \u2014 Look at the very bottom of your filter tank. There&#8217;s a drain plug (sometimes called a drain cap) that&#8217;s used to winterize the filter or drain it for service. Feel around it. Wet? That&#8217;s your problem.<\/p>\n<p><strong>2. Belly Band or Clamp<\/strong> \u2014 If you have a sand filter or certain DE filters, there&#8217;s a large band or clamp that holds the two tank halves together. Run your finger along the entire seam. Any moisture means the clamp isn&#8217;t sealing properly.<\/p>\n<p><strong>3. Plumbing Connections<\/strong> \u2014 Check where the pipes connect to the filter \u2014 both the inlet and outlet fittings at the bottom of many filters. Threaded connections and union fittings are common leak points.<\/p>\n<p><strong>4. Tank Body<\/strong> \u2014 Finally, inspect the actual tank. Look for visible cracks, especially near the bottom third where water pressure is highest. Hairline cracks can be tough to spot, so feel for wet spots on the tank surface.<\/p>\n<hr>\n<h2>How to Fix Each Type of Bottom Filter Leak<\/h2>\n<h3>Fixing a Leaking Drain Plug<\/h3>\n<p>This is the most common cause of bottom leaks, and it&#8217;s the easiest fix. The drain plug has a small O-ring or gasket that dries out, cracks, or gets damaged over time.<\/p>\n<p><strong>What you&#8217;ll need:<\/strong><\/p>\n<ul>\n<li>Replacement drain plug O-ring (match your filter brand\/model)<\/li>\n<li>Silicone-based lubricant<\/li>\n<li>Teflon tape (backup option)<\/li>\n<\/ul>\n<p><strong>The fix:<\/strong><\/p>\n<ol>\n<li>Turn off the pump and release pressure using the air relief valve on top of your filter<\/li>\n<li>Unscrew the drain plug by hand or with channel-lock pliers (be gentle \u2014 plastic threads strip easily)<\/li>\n<li>Remove the old O-ring and inspect it \u2014 you&#8217;ll probably see cracks, flat spots, or dried-out sections<\/li>\n<li>Clean the plug threads and the housing threads with a rag<\/li>\n<li>Install the new O-ring and apply a thin coat of silicone lubricant<\/li>\n<li>Thread the plug back in hand-tight, then add just a quarter turn with pliers<\/li>\n<li>Run the pump and check for leaks<\/li>\n<\/ol>\n<p><strong>Pro tip:<\/strong> Over-tightening causes more drain plug leaks than under-tightening. The O-ring does the sealing work \u2014 the threads just hold it in place. Crank it too hard and you&#8217;ll crush the O-ring or crack the plastic housing.<\/p>\n<p>A quality O-ring kit like the <a href=\"https:\/\/www.amazon.com\/dp\/B07DVLH7FH?tag=poolcalc04-20\">Replacement Pool Filter Drain Plug Kit<\/a> covers most major filter brands and costs around $8-12. Way cheaper than a service call.<\/p>\n<hr>\n<h3>Fixing a Leaking Belly Band or Tank Clamp<\/h3>\n<p>Sand filters and some DE filters use a large clamp or band to hold the tank halves together. Inside that seam sits a gasket that can fail after 5-10 years of chemical exposure and UV damage.<\/p>\n<p><strong>What you&#8217;ll need:<\/strong><\/p>\n<ul>\n<li>Replacement tank O-ring\/gasket (filter-specific)<\/li>\n<li>Silicone lubricant<\/li>\n<li>Possibly a new clamp if yours is corroded<\/li>\n<\/ul>\n<p><strong>The fix:<\/strong><\/p>\n<ol>\n<li>Turn off pump, close valves on both sides of the filter, and release pressure<\/li>\n<li>Remove the clamp \u2014 most use a single bolt or a large toggle mechanism<\/li>\n<li>Carefully separate the tank halves (have a helper if you have a sand filter \u2014 the top half is heavy)<\/li>\n<li>Remove the old gasket from the groove. It might be stuck \u2014 a flat screwdriver helps<\/li>\n<li>Clean the groove thoroughly with a damp rag. Old gasket residue prevents proper sealing<\/li>\n<li>Install the new gasket. Don&#8217;t stretch it \u2014 just lay it in the groove<\/li>\n<li>Apply silicone lubricant to the gasket surface<\/li>\n<li>Reassemble, making sure the halves seat evenly all the way around<\/li>\n<li>Tighten the clamp in stages \u2014 a little on each side, alternating, like tightening lug nuts<\/li>\n<\/ol>\n<p><strong>Warning:<\/strong> If your clamp is heavily corroded or the bolt\/threads are damaged, replace the whole clamp. A $35 clamp is cheap insurance against a catastrophic tank separation.<\/p>\n<hr>\n<h3>Fixing Leaking Plumbing Connections<\/h3>\n<p>The threaded fittings where pipes connect to your filter are under constant pressure cycling \u2014 on, off, on, off, hundreds of times per season. Eventually, Teflon tape fails, thread sealant cracks, and leaks develop.<\/p>\n<p><strong>What you&#8217;ll need:<\/strong><\/p>\n<ul>\n<li>Teflon tape (blue &#8220;monster tape&#8221; for plumbing, not white)<\/li>\n<li>Thread sealant (optional but recommended)<\/li>\n<li>Channel-lock pliers or pipe wrench<\/li>\n<li>Possibly new fittings if threads are damaged<\/li>\n<\/ul>\n<p><strong>The fix:<\/strong><\/p>\n<ol>\n<li>Turn off pump and close isolation valves<\/li>\n<li>Unscrew the leaking fitting. If it&#8217;s a union, you can usually do this by hand<\/li>\n<li>For threaded fittings, carefully back them out. Support the pipe \u2014 don&#8217;t put stress on the filter housing<\/li>\n<li>Remove all old Teflon tape and sealant residue from both male and female threads<\/li>\n<li>Apply new Teflon tape \u2014 wrap it clockwise (when looking at the end of the male threads), overlapping 50%, for 4-6 wraps<\/li>\n<li>Optional: add a thin layer of thread sealant on top of the tape<\/li>\n<li>Thread the fitting back in hand-tight, then add 1-2 turns with pliers<\/li>\n<li>Open valves and run the pump to test<\/li>\n<\/ol>\n<p><strong>Common mistake:<\/strong> Using white Teflon tape that&#8217;s too thin. Spend the extra $3 for <a href=\"https:\/\/www.amazon.com\/dp\/B000H5QXBE?tag=poolcalc04-20\">quality plumber&#8217;s Teflon tape<\/a> that&#8217;s thicker and more durable.<\/p>\n<hr>\n<h3>Dealing With a Cracked Filter Tank<\/h3>\n<p>Here&#8217;s the bad news scenario. If your leak is coming from an actual crack in the tank body \u2014 not a fitting, not a seal, the tank itself \u2014 your options are limited.<\/p>\n<p><strong>Can you repair a cracked filter tank?<\/strong><\/p>\n<p>Technically? Sometimes. Practically? Rarely worth it. Small hairline cracks in low-pressure areas can sometimes be patched with two-part epoxy or plastic welding. But pool filter tanks experience significant pressure cycling (25-30 PSI when running, 0 when off), and patches typically fail within weeks or months.<\/p>\n<p><strong>Signs it&#8217;s time for a new filter:<\/strong><\/p>\n<ul>\n<li>Crack is longer than 2 inches<\/li>\n<li>Crack is in the lower third of the tank<\/li>\n<li>You can see the crack spreading or branching<\/li>\n<li>Your filter is more than 10-12 years old<\/li>\n<li>Repair attempts have already failed<\/li>\n<\/ul>\n<p>A quality replacement cartridge filter for an average residential pool runs $300-500. Sand filters cost $400-700. It&#8217;s not cheap, but it&#8217;s cheaper than water damage to your equipment pad or constantly fighting a losing repair battle.<\/p>\n<hr>\n<h2>When to Call a Professional<\/h2>\n<p>Not every leak needs a pro. But some situations genuinely benefit from experienced hands:<\/p>\n<ul>\n<li><strong>You can&#8217;t locate the leak source<\/strong> after following the diagnostic steps above<\/li>\n<li><strong>The leak involves your multiport valve<\/strong> \u2014 these have multiple internal seals and gaskets that require disassembly<\/li>\n<li><strong>Plumbing needs rerouting<\/strong> or you&#8217;re dealing with rigid PVC that requires cutting and gluing<\/li>\n<li><strong>Your filter needs replacement<\/strong> and you want it sized correctly for your pool (undersized filters are surprisingly common)<\/li>\n<\/ul>\n<p>Expect to pay $75-150 for a diagnostic service call, plus parts and labor for repairs. Get quotes from 2-3 pool companies \u2014 pricing varies wildly.<\/p>\n<hr>\n<h2>Preventing Future Filter Leaks<\/h2>\n<p>Once you&#8217;ve fixed this leak, here&#8217;s how to avoid the next one:<\/p>\n<p><strong>Lubricate O-rings annually<\/strong> \u2014 Every spring, remove drain plugs and apply fresh silicone lubricant to O-rings. Takes 5 minutes, prevents most bottom leaks.<\/p>\n<p><strong>Don&#8217;t over-tighten anything<\/strong> \u2014 Plastic threads and O-ring seals fail from over-tightening more than under-tightening. Snug plus a quarter turn. That&#8217;s it.<\/p>\n<p><strong>Keep your pump running during chemical treatments<\/strong> \u2014 Concentrated chemicals sitting against seals and gaskets accelerates deterioration.<\/p>\n<p><strong>Monitor your filter pressure gauge<\/strong> \u2014 Normal operating pressure should stay consistent (usually 8-15 PSI for most residential systems). Sudden spikes stress seals and connections.<\/p>\n<p><strong>Check chemical balance weekly<\/strong> \u2014 Balanced water extends the life of everything in your system. Use our free <a href=\"https:\/\/poolchemicalcalculator.com\/app\">Pool Chemical Calculator app<\/a> to dial in your chlorine, pH, and alkalinity without guesswork.<\/p>\n<h2>Related Pool Care Tools and Guides<\/h2>\n<ul>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/volume\">Pool volume calculator<\/a> \u2014 confirm gallons before sizing a replacement filter or dosing chemicals.<\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/app\">Pool chemical calculator app<\/a> \u2014 calculate exact chlorine, pH, alkalinity, calcium hardness, stabilizer, and salt adjustments.<\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-pressure-too-high\/\">Pool filter pressure too high<\/a> \u2014 troubleshoot pressure spikes that can force seals to leak.<\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/news\/how-often-to-clean-pool-filter\/\">How often to clean pool filter<\/a> \u2014 keep cartridges, sand, and DE grids from overloading.<\/li>\n<\/ul>\n<hr>\n<h2>FAQ: Pool Filter Leaking From Bottom<\/h2>\n<h3>How do I know if my pool filter is leaking or just draining condensation?<\/h3>\n<p>Real leaks produce enough water to form puddles that stick around. They also continue (or worsen) when the pump is running. Condensation typically appears as light dampness on the outside of the tank on humid mornings and dries up within an hour of the pump running. If you&#8217;re seeing standing water that requires cleanup, it&#8217;s a leak.<\/p>\n<h3>Can I use Flex Seal or similar products to fix a filter leak?<\/h3>\n<p>For drain plugs and plumbing fittings? Hard no \u2014 these need proper O-rings and thread tape. For tank cracks? It might buy you a few weeks, but it&#8217;s not a permanent solution. Flex Seal isn&#8217;t designed for the pressure cycling that pool filters experience. Save yourself frustration and do the proper repair.<\/p>\n<h3>Why does my pool filter leak only when the pump turns off?<\/h3>\n<p>This typically indicates a check valve issue or a leak above the water line that only becomes visible when pressure releases. When the pump stops, water can backflow and find escape routes through compromised seals. Check your inlet\/outlet valves and any connections on the upper portion of your filter.<\/p>\n<h3>How much does it cost to fix a leaking pool filter?<\/h3>\n<p>DIY repairs range from $8-15 for O-ring replacements to $30-50 for gaskets and clamps. Professional repairs run $100-250 including labor. A complete filter replacement costs $300-700 depending on type and size. Start with the cheap fixes \u2014 drain plugs and O-rings cause 60% of bottom leaks.<\/p>\n<h3>Should I replace my pool filter or repair it?<\/h3>\n<p>Repair if: the leak is at a fitting, O-ring, or gasket, and the tank itself is intact. Replace if: the tank is cracked, your filter is over 10 years old, you&#8217;ve done multiple repairs in the past 2 years, or a repair quote exceeds 50% of replacement cost.<\/p>\n<hr>\n<h2>Keep Your Pool Running Smoothly<\/h2>\n<p>Now that you&#8217;ve tackled that filter leak, make sure the rest of your pool chemistry stays dialed in. Unbalanced water shortens the life of every component in your system \u2014 filters, pumps, heaters, and plumbing.<\/p>\n<p><strong><a href=\"https:\/\/poolchemicalcalculator.com\/app\">Try our free Pool Chemical Calculator app<\/a><\/strong> to get exact dosing recommendations for your pool size. No more guessing, no more &#8220;eyeballing it,&#8221; no more dumping in chemicals and hoping for the best. Just enter your current readings and pool volume, and we&#8217;ll tell you exactly what to add.<\/p>\n<p>Your pool deserves better than trial and error. And so does your wallet.<\/p>\n<hr>\n<p><!-- PCC RELATED LINKS START --><\/p>\n<section class=\"pcc-related-guides\">\n<h2>Related pool calculators and guides<\/h2>\n<ul>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/volume\">Pool volume calculator<\/a><\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/chlorine\">Free chlorine calculator<\/a><\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/ph\">pH calculator<\/a><\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/alkalinity\">Alkalinity calculator<\/a><\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/forecast\">Pool chemical forecast<\/a><\/li>\n<li><a href=\"https:\/\/poolchemicalcalculator.com\/news\">Pool maintenance blog<\/a><\/li>\n<\/ul>\n<\/section>\n<p><!-- PCC RELATED LINKS END --><br \/>\n<!-- PCC APP CTA START --><\/p>\n<section class=\"pcc-app-cta\" data-pcc-app-cta=\"true\">\n<h2>Get exact pool chemical doses<\/h2>\n<p>Pool Chemical Calculator turns your test readings, pool volume, and target levels into exact treatment amounts for chlorine, pH, alkalinity, calcium, stabilizer, salt, and more.<\/p>\n<p><a href=\"https:\/\/poolchemicalcalculator.com\/app\"><strong>Open the Pool Chemical Calculator app<\/strong><\/a> for iOS, Android, or web.<\/p>\n<\/section>\n<p><!-- PCC APP CTA END --><br \/>\n<!-- PCC AI SEO STRUCTURED DATA START --><br \/>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"BlogPosting\",\"@id\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/#article\",\"headline\":\"Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide\",\"description\":\"Quick Answer: A pool filter leaking from the bottom usually means one of four things \u2014 a cracked filter tank, a worn drain plug O-ring, a failed belly.\",\"url\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/\",\"mainEntityOfPage\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/\",\"image\":\"https:\/\/poolchemicalcalculator.com\/images\/cards\/Forecast-Card-01.png\",\"dateModified\":\"2026-06-19T13:04:29.751266+00:00\",\"author\":{\"@type\":\"Organization\",\"name\":\"Pool Chemical Calculator\"},\"publisher\":{\"@type\":\"Organization\",\"name\":\"Pool Chemical Calculator\",\"url\":\"https:\/\/poolchemicalcalculator.com\"}},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/poolchemicalcalculator.com\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Pool Care Blog\",\"item\":\"https:\/\/poolchemicalcalculator.com\/news\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide\",\"item\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/\"}]},{\"@type\":\"SoftwareApplication\",\"@id\":\"https:\/\/poolchemicalcalculator.com#app\",\"name\":\"Pool Chemical Calculator\",\"applicationCategory\":\"UtilitiesApplication\",\"operatingSystem\":\"iOS, Android, Web\",\"url\":\"https:\/\/poolchemicalcalculator.com\/app\",\"downloadUrl\":[\"https:\/\/itunes.apple.com\/us\/app\/pool-chem-calculator\/id1453351222\",\"https:\/\/play.google.com\/store\/apps\/details?id=com.poolchemicalcalculator.poolcalc\"],\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"USD\"}},{\"@type\":\"FAQPage\",\"@id\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/#faq\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"How do I know if my pool filter is leaking or just draining condensation?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Real leaks produce enough water to form puddles that stick around. They also continue (or worsen) when the pump is running. Condensation typically appears as light dampness on the outside of the tank on humid mornings and dries up within an hour of the pump running. If you're seeing standing water that requires cleanup, it's a leak.\"}},{\"@type\":\"Question\",\"name\":\"Can I use Flex Seal or similar products to fix a filter leak?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"For drain plugs and plumbing fittings? Hard no \u2014 these need proper O-rings and thread tape. For tank cracks? It might buy you a few weeks, but it's not a permanent solution. Flex Seal isn't designed for the pressure cycling that pool filters experience. Save yourself frustration and do the proper repair.\"}},{\"@type\":\"Question\",\"name\":\"Why does my pool filter leak only when the pump turns off?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"This typically indicates a check valve issue or a leak above the water line that only becomes visible when pressure releases. When the pump stops, water can backflow and find escape routes through compromised seals. Check your inlet\/outlet valves and any connections on the upper portion of your filter.\"}},{\"@type\":\"Question\",\"name\":\"How much does it cost to fix a leaking pool filter?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"DIY repairs range from $8-15 for O-ring replacements to $30-50 for gaskets and clamps. Professional repairs run $100-250 including labor. A complete filter replacement costs $300-700 depending on type and size. Start with the cheap fixes \u2014 drain plugs and O-rings cause 60% of bottom leaks.\"}},{\"@type\":\"Question\",\"name\":\"Should I replace my pool filter or repair it?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Repair if: the leak is at a fitting, O-ring, or gasket, and the tank itself is intact. Replace if: the tank is cracked, your filter is over 10 years old, you've done multiple repairs in the past 2 years, or a repair quote exceeds 50% of replacement cost.\"}}]},{\"@type\":\"HowTo\",\"@id\":\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/#howto\",\"name\":\"Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide\",\"description\":\"Quick Answer: A pool filter leaking from the bottom usually means one of four things \u2014 a cracked filter tank, a worn drain plug O-ring, a failed belly.\",\"step\":[{\"@type\":\"HowToStep\",\"position\":1,\"name\":\"Turn Off Your Pump and Observe\",\"text\":\"Kill the power to your pump completely. Not just the timer \u2014 flip the breaker. Now watch the filter for 5-10 minutes. Does water keep dripping? A leak that continues when the pump is off tells you it's gravity-related (drain plug, tank crack below water line). A leak that stops immediately points to pressure-related issues (clamp seals, plumbing fittings).\"},{\"@type\":\"HowToStep\",\"position\":2,\"name\":\"Dry Everything and Watch\",\"text\":\"Grab some old towels and wipe down the entire filter housing, every fitting, and the base. Get it bone dry. Now turn the pump back on and watch closely for 2-3 minutes. The first spot to get wet reveals your leak source.\"},{\"@type\":\"HowToStep\",\"position\":3,\"name\":\"Check These Four Common Culprits\",\"text\":\"Run through this checklist in order:\"}]}]}<\/script><br \/>\n<!-- PCC AI SEO STRUCTURED DATA END --><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Quick Answer: A pool filter leaking from the bottom usually means one of four things \u2014 a cracked filter tank, a worn drain plug O-ring, a failed belly.<\/p>\n","protected":false},"author":4,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"googlesitekit_rrm_CAowle7eCw:productID":"","footnotes":""},"categories":[1],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v20.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide - Pool Chemical Calculator<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/poolchemicalcalculator.com\/news\/pool-filter-leaking-from-bottom\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Pool Filter Leaking From Bottom: Fix It Fast With This Troubleshooting Guide - 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