Pentair Tagelus Sand Filter

The Tagelus is Pentair's fiberglass top mount sand filter: a one-piece fiberglass-reinforced tank on a foot, with a six-position Hi-Flow multiport valve clamped to the top. Pentair's 2025 manual covers four sizes, the TA 40D, TA 50D, TA 60D and TA 100D, plus a TA 60 with ClearPro.

The valve comes with it. That's the difference from Pentair's side mount Triton II, which ships without one. The unions don't: Pentair's catalog says they're sold separately.

It isn't the Sand Dollar either, though it looks similar from across the yard. The Sand Dollar is Pentair's top mount filter with a thermoplastic tank. The two share the same 190059 pressure gauge, and Pentair's valve page lists one 2 inch valve, 263085, for both the TA 60 and the Sand Dollar SD 80.

Which sizes Pentair still sells

It depends which Pentair document you read.

• The 2025-2026 catalog lists three items: the TA 60D (145241), the TA 100D (145240) and a TA 60D with a 2 inch valve (145385).
• The product page lists those three, two more dealer items, 144126 and 144127, without naming their models, and online versions EC-145240 and EC-145241. It says the 40, 50 and 60D come standard with a plastic clamp; the catalog says the 40 and 60D.
• The July 2025 manual covers the TA 40D, TA 50D, TA 60D, TA 100D and the TA 60 with ClearPro.

All three of the catalog's items are on Pentair's TradeGrade list, which matters for the warranty.

Flow, and how big a pool it suits

Pentair's figures:

• TA 40D: 1.8 sq. ft., 40 GPM
• TA 50D: 2.3 sq. ft., 50 GPM
• TA 60D: 3.1 sq. ft., 60 GPM
• TA 100D: 4.9 sq. ft., 100 GPM

The brochure calls these the maximum flow rate, so don't put a pump on the filter that pushes more.

Compare the TA 100D with the Triton II's TR 100. Both have about 4.9 square feet of sand. Pentair rates the Tagelus at 100 GPM, about 20 GPM per square foot, and the TR 100 at 74, because the Triton's larger sizes are rated at 15 GPM per square foot. Same sand area, different rating basis. The filter sizing guide covers matching filter to pump.

Pentair's manual says the system must turn the pool over at least twice a day. At rated flow, 12 hours of running moves 28,800 gallons on the TA 40D, 36,000 on the TA 50D, 43,200 on the TA 60D and 72,000 on the TA 100D.

The valve

Pentair's brochure describes a six-position Hi-Flow valve with a sight glass and a manual air relief. The TA 100D is the exception on the air relief: every start-up and backwash step in the manual that opens the air bleeder says "except TA100D".

Pentair's valve page lists these for the Tagelus:

• 262506: 1½ inch clamp valve for the TA 30, 40, 50 and 60D, 6 inch neck
• 261185: 2 inch clamp valve, TA 100D only, 8 inch neck
• 263085: 2 inch clamp valve for the TA 60, Sand Dollar SD 80 and Cristal-Flo II 26, without unions
• 262525: the same valve with unions
• 262505: a kit with valve that converts an older threaded TA filter to the clamp style
• 262504 and 261124: 1½ inch threaded valves for older TA filters, buttress thread and V-thread

The older threads matter. Pentair's parts sheet says Tagelus filters made before November 1, 1991 have a V-thread top and valve, and later ones a buttress thread, and it says in capitals not to interchange thread types. Check the serial number before you order a valve: the first four digits are the month and year the filter was made.

Pool valves explained covers what each multiport position does.

Installing it

Pentair's manual says only a qualified professional should install the filter. Its guidelines are the same as for its other sand filters:

• A permanent slab, preferably poured concrete, or a platform of concrete block or brick.
• No electrical controls over the filter, and room to stand clear when the pump starts. The minimum clearances are on a large label on the tank.
• A check valve between the filter and heater, to stop hot water backing up.
• A vacuum breaker if the backwash line runs more than 40 feet, or discharges more than 10 feet below the pool water surface.
• No pump with a shut-off pressure of 50 psi or more. The filter's maximum is 50 psi.
• The chlorinator downstream of the filter, with a check valve between them.
• No positive shut-off valve at the filter outlet. With one closed, the internal air relief can't work.
• Pool chemicals at least 10 feet away. Pentair says fumes and spills can weaken the filter's parts until the valve separates.
• Never pressure test it with air or gas.

Leave headroom. Pentair's clearance to lift the valve and internal piping out runs from 47 inches on the TA 40D to 65.5 inches on the TA 100D. Under a low roof or a deck, that's the number that decides whether it fits.

Sand, and the weights that disagree

Pentair's manual specifies No. 20 standard silica sand, 0.018 to 0.022 inch, with a uniformity coefficient of 1.75 or less.

Here's the problem. The July 2025 manual gives these amounts:

• TA 40D: 125 lb, with 7.75 inches of freeboard
• TA 50D: 175 lb, with 9.25 inches of freeboard
• TA 60D: 275 lb, with 10.25 inches of freeboard
• TA 100D: 450 lb, with 11.25 inches of freeboard

The 2019 brochure says 175, 225, 325 and 600 lb, and the 2025-2026 catalog agrees with the brochure for the TA 60D and TA 100D. That's 50 to 150 lb more at every size.

The manual settles it for you. It calls freeboard, the gap between the top of the tank and the sand bed, the most important variable, and says sand density varies, so the weights are for reference only. Fill to the freeboard, not the bag count. Buy the bigger number and keep what's left.

To fill it:

1. Put the sand guide in the top of the tank and fill the tank about half full of water.
2. Pour the sand in slowly until it reaches the freeboard for your size.
3. Take the sand guide out.
4. Clear any sand spilled around the opening.
5. Clean the sealing surfaces and lightly coat the valve o-ring with silicone lubricant.
6. Fit the valve following the valve's own manual, which comes with it.

The clamp and the quad ring

On a Tagelus the valve is held on by a clamp, and the tank has a threaded valve adapter at the top with a quad ring under it. A new tank and foot comes with the adapter already fitted.

Pentair's tightening spec for the adapter: lubricate the quad ring with silicone lubricant, then tighten it hand tight plus at least a quarter turn on the TA 40D, TA 50D and TA 60D, and hand tight plus at least three quarters of a turn on the TA 100D. Filters made before September 2017 have an o-ring there instead of a quad ring.

Pentair's warning is blunt: trapped air can launch the closure with deadly force, and on a Tagelus the closure is the valve. Before touching the valve or clamp, turn off power to the pump and any automatic controls at the breaker, open the air bleeder, and wait until all the pressure is gone. Never adjust or tighten anything while the system is pressurized or the pump is on.

Two more from the manual:

• Replace a clamp that's corroded, deformed or otherwise damaged. Pentair says defective parts can let the filter separate.
• Mind your hands around the clamp. Pentair says the manufacturing process can leave sharp edges on some parts.

Starting it up

1. On a new pool, clean the pool before filling it.
2. Open the backwash line and put the valve on Backwash.
3. Fill the pump's strainer pot if it needs it, and check the valve clamp is tight.
4. Open the manual air bleeder (not on the TA 100D), stand clear of the filter, and start the pump.
5. Close the bleeder once the air is out and a steady stream of water comes out.
6. Keep backwashing until the waste water is as clear as the pool. Pentair says shipping can abrade the sand enough to make this first backwash take longer.
7. Stop the pump, set the valve to Filter, and check the suction and return lines are open.
8. Open the bleeder again, stand clear, start the pump, and close the bleeder once water runs steady.
9. Write down the operating pressure. Everything after this compares to it.

Always turn the pump off before moving the valve. Pentair repeats it in both the start-up and the backwash instructions.

When and how to backwash

Don't backwash on a schedule. Pentair's manual says backwashing too often leads to poor filtration, and that weather, rain, dust, pollen and water temperature all change how often it's needed.

• On a new pool: backwash after the first 48 hours, to clear plaster dust and construction debris.
• With a flow meter: backwash when flow is 30% below a freshly backwashed filter.
• Without one: backwash when the gauge reads 10 psi above its reading just after a backwash.

The steps:

1. Stop the pump, open the backwash line, and set the valve to Backwash.
2. Stand clear, start the pump, and backwash for about 3 to 5 minutes, or until the water runs clean.
3. Stop the pump, set the valve to Rinse, start it and rinse for about 30 seconds.
4. Stop the pump, set the valve to Filter, and check the return line is open.
5. Open the air bleeder (not on the TA 100D), stand clear, start the pump, and close the bleeder once water runs steady.

If the pressure right after a backwash is 4 to 6 psi above the original start-up reading, Pentair says the sand bed needs a chemical clean. How to backwash a sand filter covers the steps for any make.

Chemical cleaning

Pentair says to get a sand filter cleaner from a pool supplier, which removes oils, scale and rust, and to mix it per its label.

1. Backwash the filter.
2. Shut the pump off, open the filter drain and let the filter empty, closing valves first if the filter sits below the pool's water level.
3. Close the drain and set the valve to Backwash.
4. Clean the pump basket, pour the solution into the strainer pot and put the lid back.
5. Open those valves slightly again if you closed them, and run the pump for about three minutes.
6. Shut it off, leave the valve on Backwash, and disconnect power to the pump and controls.
7. Let the solution soak the sand bed overnight, then backwash.

Winterizing

1. Backwash the filter.
2. Shut the pump off and open the air bleeder (not on the TA 100D).
3. Turn the valve to Winterize and leave it there until spring.
4. Remove the drain plug and store it.
5. Drain the system's piping.
6. Cover the filter with a tarp or plastic sheet.

If you blow the lines out with compressed air, Pentair says to make sure the filter's air relief is open first, or the valve can separate violently. Closing a pool for winter covers the rest of the system.

What the troubleshooting table says

Water not clean enough: unbalanced chemistry, backwashing too often, the wrong amount or size of sand, or not running the system long enough.

High filter pressure: not enough backwashing, debris or mineral deposits in the sand bed, or a partly closed valve or blockage in the return line.

Short filter cycles: poor backwashing, unbalanced chemistry, a flow rate that's too high, or a dirty or worn-out sand bed. For deposits, Pentair's fix is to remove the top inch of sand, replace it and chemically clean the filter. If the sand has eroded over time, replace the whole bed.

Low flow at the returns with low filter pressure: a clogged pump basket, a blockage in the pump, or a blockage in the suction line.

Sand coming back into the pool: a damaged lateral, a backwash flow rate that's too high, or a damaged or missing valve air strainer. Sand in the pool works through all three.

Looking after the tank

Wash the outside with mild detergent and water, and no solvents. For internal work, Pentair says to remove the whole drain spigot at the bottom and flush the tank out with a garden hose; its Sand Vacuum, 542090, also works. After years in the sun the tank can turn foggy or rough, and Pentair says it can be painted, but not the valve.

Buying one

The TA 60D, the TA 60D with a 2 inch valve and the TA 100D are on Pentair's TradeGrade list. Pentair says those are meant for retail stores, pool builders and pool service companies, and that in-ground TradeGrade products carry full parts and labor coverage.

The EC- versions are Pentair's online items, and Pentair's warranty page gives anything bought online one year, parts only, with no labor. Either way, budget for unions.

Where Pentair's documents disagree

• The sand. The 2025 manual's weights are 50 to 150 lb lower at every size than the 2019 brochure's, and the 2025-2026 catalog sides with the brochure for the two sizes it lists. The manual's freeboard is what to fill to.
• Which sizes are current. The catalog lists three items; the product page lists five dealer items and two online ones; the manual covers four sizes and a ClearPro.
• The plastic clamp. The product page says the 40, 50 and 60D come with one; the catalog says the 40 and 60D.
• Where to buy it. The product page says it's available only in-store from dealers or retail stores, above an item table listing two EC- versions as available online.
• The part numbers. Pentair's older parts sheet, from an earlier parts catalog, gives different numbers from the 2025 manual for the 6 inch valve adapter (154555 against 152520), the TA 100D's adapter (154521 against 157093), its clamp (152130 against 272619), the valve adapter o-rings, and most of the piping assemblies. This page follows the 2025 manual. If you have an older filter, the sheet covers the TA 30 and TA 35 too, which the manual doesn't.
• The TA 60 with the 2 inch valve. Pentair's 2019 parts list for it gives piping 152237 and six ClearPro laterals, 150088. The 2025 manual lists neither against a TA 60D, and gives the ClearPro laterals only to the TA 60 ClearPro.
• The turnover figures. The brochure gives 28,000 gallons for the TA 40D at 12 hours and the TA 60D at 8 hours. At the rated flow both are 28,800, which is what the catalog prints for the TA 60D.
• The flow-meter example. The manual says to backwash when flow is 30% lower, then gives the example of 60 GPM falling to 40 GPM. That's a third lower; 30% below 60 is 42.
• Older filters. The manual says to call Pentair for part numbers on filters made before November 1994. The parts sheet documents thread changes in November 1991 and a port change in April 1993.