D.E. Filter Grid Replacement Guide

D.E. (diatomaceous earth) filters give some of the clearest water of any pool filter, but they depend on fabric-covered grids to hold a thin layer of D.E. powder. When a grid tears or a manifold cracks, powder ends up in the pool and the water gets cloudy. This guide explains how to tell when grids need replacing, how to choose the right ones, and how to put the filter back together. For routine backwashing and cleaning, see our D.E. Filtration Maintenance page.

Signs your grids or manifold need attention

• D.E. powder blowing back into the pool through the return jets, often right after you add fresh D.E.
• Cloudy water that doesn't clear, even with good chemistry and run time
• Torn, worn-thin, or frayed fabric, or fabric pulling away from the grid frame
• Cracked or broken grid frames or end caps
• Pressure that climbs very quickly after cleaning, which can mean the fabric is clogged with oils or minerals that cleaning won't remove

D.E. in the pool doesn't always mean a torn grid. A cracked manifold, a missing or damaged O-ring, a grid not seated in its manifold port, or a damaged internal air bleed can also let powder through. Inspect everything when you open the filter.

Know your filter type

There are two main D.E. filter designs:

• Vertical grid filters use several fan-shaped grids arranged in a circle around a central standpipe and held by a top manifold. Most residential models use a set of full-size grids plus one shorter partial grid that leaves room for the standpipe or air bleed. A common arrangement is seven full grids and one partial, but check your filter's manual.
• Spin/bump or flex-tube filters use many fabric tubes instead of fan-shaped grids. They use different replacement parts.

Your filter's model number, usually on the tank label, tells you which grids fit. The filter's area in square feet (for example 36, 48, or 60) also determines grid size. Grids from different filter sizes aren't interchangeable.

Choosing replacement grids

• Individual grids or a full set: If only one grid is damaged and the rest are in good shape, replacing just that one can make sense. If several are worn or the filter has many seasons on it, a full set gives you even performance and saves a second teardown soon after.
• Original or compatible: Compatible aftermarket grids are made to fit specific filter models. Check that the size, height, and the shape of the grid's neck that fits the manifold match your filter.
• Related parts: While the filter is apart, look at the manifold, the bottom spreader or support, the tank O-ring, and the air bleed. Order these at the same time if they're worn.

Shop grids, grid sets, and manifolds in D.E. Filter Grids & Manifolds, and tank O-rings, clamps, and gauges in Filter Parts & Accessories.

Step-by-step: replacing D.E. grids

Safety note: Turn the pump off at the breaker or control, close the valves that isolate the filter if you have them, and open the air relief valve to release all pressure before loosening the clamp or tank bolts. A filter under pressure can separate violently. Wear a dust mask when handling dry D.E. powder.

1. Drain the tank using the drain plug at the bottom of the filter.
2. Open the tank by removing the clamp band or lid following your filter's manual. Lift off the top half of the tank.
3. Remove the grid assembly. Lift the manifold and grids out as a unit, usually after removing a retaining nut or rod. Note how the grids sit and where the partial grid goes. A quick phone photo helps.
4. Hose off the assembly to remove old D.E., then separate the grids from the manifold.
5. Inspect every part: each grid's fabric and frame, the manifold for cracks, the bottom spreader, and all O-rings.
6. Install the new grids into the manifold, placing the partial grid where the old one was. Each grid should sit fully in its port.
7. Reassemble the assembly into the tank and tighten the retaining hardware snugly.
8. Replace or lubricate the tank O-ring with a silicone-based pool lubricant, then refit the tank top and clamp, following your manual for clamp tightening.
9. Restart the pump with the air relief valve open, and close it when a steady stream of water comes out.
10. Add fresh D.E. through the skimmer, in the amount listed on your filter's label or in the manual. The amount depends on the filter's square footage, and too much or too little causes problems.
11. Record the new clean pressure as your baseline.

Disposing of old D.E.

Check local rules before backwashing or rinsing D.E. into a yard, street, or storm drain. Some areas restrict where D.E. can go. Many owners use a separation tank or let the D.E. settle and dispose of it as solid waste.

Making new grids last

• Never run a D.E. filter without a fresh coating of D.E. on the grids. Bare fabric clogs quickly with fine dirt and oils.
• Clean or backwash when pressure rises above your baseline as your manual recommends, and do a full teardown cleaning at least once a year.
• Use a filter cleaner for oils and minerals if pressure stays high after cleaning.
• Keep pH and calcium balanced to slow scale buildup in the fabric.

If the tank itself is cracked or the filter is near the end of its life, compare options in Choosing the Right Filter and our Pool Filters collection.

Not sure which grid set fits your filter? Use the chat on this page or reach us through our contact page with your filter's model and size, and we'll help you find the right grids.