Culex mosquitoes lay their eggs on the surface of fresh or stagnant water. The water may be in tin cans, barrels, horse troughs, ornamental ponds, swimming pools, puddles, creeks, ditches, or marshy areas. Mosquitoes prefer water sheltered from the wind by grass and weeds.

Culex mosquitoes usually lay their eggs at night. A mosquito may lay a raft of eggs every third night during its life span.

Culex mosquitoes lay their eggs one at a time, sticking them together to form a raft of from 200- 300 eggs. A raft of eggs looks like a speck of soot floating on the water and is about 1/4 inch long and 1/8 inch wide.

Tiny mosquito larvae emerge from the eggs within 24 hours. ( source )

If pool owners keep a constant chlorine or bromine residual in their pools, mosquitoes will seek other places to lay eggs because the presence of chlorine/bromine in a body of water makes the water unusable as place for their young to hatch and develop.

So… in the interest of keeping mosquito populations down this Summer, we urge all swimming pool owners to test and maintain chlorine/bromine levels in their pools on a regular basis. It only takes a few days for some species of mosquitoes to go from eggs to full-grown bloodsuckers!

Suggested Testing Methods for Chlorine/Bromine Levels

So by simply making sure you have an adequate chlorine or bromine residual in your swimming pool, you can do a lot help reduce the number of bloodsucking mosquitoes in your neighborhood this Summer.

Need a Chlorine or Bromine Dispenser for Your Pool?

Take a look at the selection of automatic chemical feeders available from In the Swim a leading online retailer of swimming pool equipment, parts, and chemicals.

You can also get granular chlorine, chlorine sticks and calcium hypochlorite granules at In the Swim.

Hi. Do chlorine test kits work for bromine, too?

Yes, Stacey, you can use a DPD-based chlorine test kit to detect bromine levels in water. Oh, and since you’ve asked about bromine, we will assume you want to test pool or hot tub water… so you can expect us to arrive shortly for the pool party. 😛

Generally speaking, and as long as you follow the directions for testing chlorine in water using a DPD-based water test kit, you will simply have to multiply the results of the test by 2.25 if you have bromine in the water instead of chlorine.

In other words, if you got a reading of 1.0ppm chlorine, but the water actually contained bromine, you have a concentration of 2.25ppm bromine in the water.

That’s too much math for me! My brain hurts!

For those of you NOT interested in having to perform any sort of mathematical calculations poolside, many pool & spa test kits come with color charts/labels for both chlorine and bromine.

And then, for the folks who don’t want to do any math OR have to compare colors of liquids to a color chart or color comparator, we have meters such as the eXact Micro 7+ Pool/Spa Testing Meter which takes ALL the guesswork out of chlorine and bromine testing!

Last we checked, the eXact Micro 7+ Pool/Spa Testing Meter qualified for free shipping at FilterWater.Com.