Getting large amounts of iron in your pool water can be a frustrating problem for pool owners. To make it worse, it was most likely added unknowingly.
While not inherently dangerous to swimmers, iron can cause unsightly staining, turn your water rusty or green, and interfere with chemical balance.
The only surefire way to get rid of iron in the pool is by draining it and replacing it with fresh water. Because of this, understanding how it gets into the pool and preventing it from turning into a water issue is the best course of action.
How Iron Gets Into Your Pool
Iron often enters pool water through filling up the pool with well water. You’d be surprised with how much iron and other metals like copper can be present in their source water. You should make it a habit of getting your well professionally tested once a year to know exactly what is going into the pool!
Even if you’re not using well water, iron can still enter your pool through environmental runoff. Rainwater can carry soil, fertilizers, or rust from nearby structures, all of which may introduce iron.
Additionally, old or corroding metal parts inside your pool system, like ladders, pipes, heaters, or fittings, can slowly release iron into the water over time. The problem can be expedited if your water chemistry is unbalanced.
Effects of Iron in Water
Iron can cause noticeable problems in a pool. The most common issue is staining. Iron tends to create rusty brown or orange stains on pool walls, steps, and liners. It is especially noticeable in pools with light-colored surfaces.
Water containing iron may also take on a brown, yellow, or greenish tint after chlorine is added, which oxidizes the metal. This discoloration not only makes the water look dirty but can be mistaken for algae or other contamination
How to Get Rid of Iron From the Pool
The most effective long-term solution to remove iron from the pool is to partially or completely drain the pool and refill it with fresh water.
If draining the pool is not feasible, you can manage the iron content by using a metal sequestrant. This binds with the iron in the water, keeping it in a soluble form that won’t stain or discolor the pool.
Prevents the formation of metal and mineral staining of pool surfaces
While sequestrants don’t remove the iron, they prevent it from oxidizing and causing problems. You’ll need to add sequestrants regularly, as they break down over time.
Preventing Iron from Getting In
Prevention is key to avoiding iron problems in the future. One of the easiest and most effective steps is to use a hose filter whenever filling or topping off your pool.
These filters are designed to remove metals like iron before they reach your pool.
If you rely on well water for larger fills, it may be worth investing in a whole-house filtration system or pre-treating the water you plan to use in the pool.
Maintaining your pool equipment also helps. Inspect ladders, rails, and plumbing for signs of rust or corrosion and replace them as needed. Older heaters, in particular, can be a hidden source of metal contamination.
If you Start to Notice Stains
If you start to see stains that look like iron, rub a vitamin C tablet on it to confirm.
Vitamin C, also known as ascorbic acid, is the best treatment for these stains. If the stains are small and sporadic, simply rubbing tablets against the stain will work.
However, if you have larger stains, an ascorbic acid treatment will be necessary.
Ironing Out Any Issues
Iron in pool water can be a nuisance, but it’s manageable with the right approach.
Take steps to prevent iron from entering the pool in the first place. With consistent maintenance and preventive care, you can enjoy clear, stain-free water all season long.