Shrimp SD › San Diego tap water
Local water guide
Is San Diego tap water good for shrimp?
It depends which shrimp. San Diego tap is hard and chloraminated: a gift for Neocaridina once it is treated, and a wall for Caridina. Here is what to do about it, shrimp by shrimp.
The short answer
Neocaridina and Amano: yes, with a conditioner that neutralizes chloramine. Caridina: no, build your water from RO.
Two facts about our supply decide everything. The water is hard, and it is chloraminated. For reference, the City of San Diego’s 2025 water quality report lists average total hardness around 237–243 ppm (roughly GH 13), TDS about 530–590 ppm, alkalinity about 110–120 ppm and pH around 8.3, with a chloramine residual averaging 1.75 ppm. Your own tap can differ by neighborhood and season, so test it. Hardness is an advantage for some shrimp and a problem for others. Chloramine is a problem for all of them until you deal with it.
Chloramine: the part that catches people out
You may have heard that you can leave tap water in a bucket overnight and the chlorine will evaporate. That advice dates from when supplies used free chlorine. San Diego’s water is chloraminated, and chloramine does not gas off. A bucket left on the counter is exactly as dangerous in the morning as it was at night.
Treat every batch of tap water with a conditioner that neutralizes chloramine, every time, or filter it through a carbon block rated for it. Skipping this once is enough to lose a colony.
What it means for each shrimp
| Neocaridina | Works as it comes. Cherry, blue dream and the other color morphs want GH 6–8 and TDS 150–250, and San Diego tap runs a little harder than that (the city’s 2025 report: GH about 13, TDS 530–590 ppm, pH about 8.3). Hardy Neocaridina cope with it. Treat it for chloramine and use it, or cut it with RO for the best colour. No remineralizer needed. |
|---|---|
| Amano shrimp | Wide tolerance. Tap is fine once treated. |
| Tiger shrimp | The most forgiving Caridina, and often keepable on cut tap water. Mix tap with RO to bring hardness down rather than using straight tap. |
| Crystal red / black, Taiwan bees | Unusable. Tap is hard and buffered where these need soft, acidic water. No additive converts it. You need RO or distilled water, a GH-only remineralizer and active buffering soil. |
See Neocaridina vs Caridina for how to choose, and the water parameter reference for every number.
Measure yours, don’t assume
Tap supplies can vary by neighborhood and season, so the numbers above describe our water in general, not your faucet in particular. Two cheap checks tell you what you actually have:
A TDS meter
The cheapest instrument in the hobby. It does not tell you what is in the water, but it tells you the moment something changes, which is what shrimp react to.
A GH test
GH is the calcium and magnesium shrimp build their shells from, and the number that matters most. Test it on your tap and again on any mixed water.
A free sample test
Bring a sample in a clean container to either Pet Zone store and we will test it. For Caridina, bring your mixed RO-plus-remineralizer water, not tap.
Changing water without killing anything
Shrimp react to the rate of change far more than to the values themselves. Keep water changes small and frequent (ten to fifteen percent weekly is plenty for a lightly stocked tank), match the new water’s temperature and TDS to the tank, add it slowly, and drip acclimate new arrivals over an hour or more.
Copper overrides every rule on this page. It is lethal to every shrimp at doses that are harmless to fish, and it shows up in some fish medications and snail treatments. Read the label before anything goes in a shrimp tank.
Questions we get asked
Is San Diego tap water safe for shrimp?
Yes for Neocaridina and Amano, as long as you neutralize chloramine first. San Diego tap is hard, a little harder than ideal but workable for Neocaridina, so it needs only a conditioner. It is not suitable for Caridina such as crystal reds and Taiwan bees.
Does chlorine evaporate out of San Diego tap water overnight?
No. The supply is chloraminated, and chloramine does not gas off the way free chlorine did. Leaving a bucket out does nothing. Use a conditioner that neutralizes chloramine every time, or remove it with a carbon block rated for it.
Can I use San Diego tap water for crystal red shrimp?
No. It is hard and buffered, the opposite of what crystal red and Taiwan bee shrimp need, and no additive converts it. Caridina need RO water, a GH-only remineralizer and active buffering soil. Tiger shrimp are the exception and are often keepable on cut tap water.
How do I know what is in my tap water?
Measure it. Tap supplies can vary by neighborhood and season, so use a TDS meter and test GH, and bring a sample in a clean container to either Pet Zone store, where water testing is free.
Keep reading
Neocaridina care
One species, every color, and why San Diego tap already suits them.
Neocaridina vs Caridina
Which to keep, and why you cannot house them together.
Caridina care
Soft water, active soil and the patience these shrimp demand.
Water parameters
The numbers for every shrimp we sell, in one table.
Bring a water sample, we’ll test it
Not sure what is coming out of your tap? Bring a sample to the Convoy store and we will test it and tell you honestly which shrimp it suits. Our Neocaridina are held on San Diego tap water, so a local Neocaridina tank is the same water they grew up in.
Or visit us at 4160 Convoy St, San Diego — open seven days, 10am–6pm.