High Tide Aquatics

Oakland/SF Tap Water

SeanMc

Supporting Member
Does anyone use tap water in SF or Oakland for their aquarium?

I'm in Oakland. My TDS meter says it's about 30 ppm. Is that good enough to make salt water and top off? The modern trend seems to prioritize stability above all else. If the tap's always the same, maybe it could work. You'd have to do something about the chlorine, obviously.

I was in OC for the holidays and stopped by a few locals stores. My favorite of them, Amazing Aquariums & Reefs, had some nice old tanks. Many had some legitimately large pieces, including an elegance coral that was basketball sized. They were all bare bottoms and I was impressed with how crusty with coralline many of the tanks were. It seemed pretty clear he was having long term success with some of these pieces and it turns out the shops has been open for over 10 years.

Anyways, I told the owner, Ali, I lived in Oakland and he was saying the tap water is so good you don't even need an RO unit. Obviously, he doesn't live in the bay area, so what does he know, but it struck me as plausible. I know the water is very low TDS for a tap, famously tastes good, and other orchid nerds seem to think we're lucky.

I wanted to ask the club if anyone has actually tried it. I know it's not ideal and the armchair answer is clearly don't risk it, but RO units are so wasteful and installing one in my apartment is a legitimate headache. I'm tempted to try it if no one else has.
 
My tap is 54. I tried it about 10 years ago. Just to see what happens. It grew lots of hair algae. I thought it would pass but it didn’t. I noticed that when my rodi gets above 2. I start growing hair algae. If you watch jake Adam’s. In one of his videos. He says his water was good. And he ran it thru like 5 di cambers to clean the rest of it up.
@boun11 he lives in Berkeley. He uses tap water. Hopefully he will chime in.
 
I've always used RODI in Oakland despite the low TDS. The good thing is that your DI resin lasts years at least. Tapping it off the carbon block to use as your drinking water helps a lot too given how many PFAS and other nasty things are showing up in our supplies. If you're worried about waste, T it off the waste water into a bucket and flush your toilets with it.
 
I remember there's detectable phosphate in the tap water though tds is low. Despite that, I used to use tap water for my 30g. It was fine in my case. Corals did thrive. I eventually started only using rodi though because that will make you feel safer when your tank is fully established full of grown-up corals.
 
When I use to make water -use to use a 3 chamber with a sediment filter and two carbon blocks and then go through a two canister with DI resin. In the three years -never changed out anything in the first canister & a big bag of DI from BRS would last a year.

Now get it from High Tide-same source as @Thales -I would be careful using straight up tap due to chloramines-that I know EDMUD uses in their water
 
I was in OC for the holidays and stopped by a few locals stores. My favorite of them, Amazing Aquariums & Reefs, had some nice old tanks. Many had some legitimately large pieces, including an elegance coral that was basketball sized. They were all bare bottoms and I was impressed with how crusty with coralline many of the tanks were. It seemed pretty clear he was having long term success with some of these pieces and it turns out the shops has been open for over 10 years.

Ali is an amazing Reefer, but I would still use an RODI, or at least a DI.

His shop is awesome. We used to go there to hang out after hours.
 
Well if you decide to use tap, you definitely need to worry about chloramines in the water, I'm not sure what EBMUD uses but I'm assuming the whole region does similar bits with disinfecting water.

As for wasting water... I'm ok with that if it's cheaper than resin replacement, at the end of the day whether you waste it by watering stuff in your yard, or it goes down the drain, it'll eventually make it's way back to where it started
 
Does anyone use tap water in SF or Oakland for their aquarium?

I'm in Oakland. My TDS meter says it's about 30 ppm. Is that good enough to make salt water and top off? The modern trend seems to prioritize stability above all else. If the tap's always the same, maybe it could work. You'd have to do something about the chlorine, obviously.

I was in OC for the holidays and stopped by a few locals stores. My favorite of them, Amazing Aquariums & Reefs, had some nice old tanks. Many had some legitimately large pieces, including an elegance coral that was basketball sized. They were all bare bottoms and I was impressed with how crusty with coralline many of the tanks were. It seemed pretty clear he was having long term success with some of these pieces and it turns out the shops has been open for over 10 years.

Anyways, I told the owner, Ali, I lived in Oakland and he was saying the tap water is so good you don't even need an RO unit. Obviously, he doesn't live in the bay area, so what does he know, but it struck me as plausible. I know the water is very low TDS for a tap, famously tastes good, and other orchid nerds seem to think we're lucky.

I wanted to ask the club if anyone has actually tried it. I know it's not ideal and the armchair answer is clearly don't risk it, but RO units are so wasteful and installing one in my apartment is a legitimate headache. I'm tempted to try it if no one else has.
Yes I have lots of coral, 2 clowns, stars & shrimp no issues except for algae and diatoms which I truly dont mind as I clean my glass daily.

I do plan to buy a used rodi in the future for peace of mind but for the time being I've had zero issues

however I'm no veteran/expert so take my experience with a pinch of salt
 
Mine is between 24-28 TDS - still use the four-stage RODI for the fish, and 3 stage RO for my drinking water. Why would you want to take shortcuts? Save on the light but not on the water quality.
 
Also keep in mind TDS measured by conductivity doesn’t measure everything in the water, only dissolved ions. So things that aren’t ionic don’t register, like pesticides, petroleum products, pharmaceuticals, PFAS, bacteria, viruses, etc.

And some contaminants are dangerous at very low levels. 1 ppm of NaCl is completely fine. 1 ppm of lead, copper, arsenic, etc isn’t.

Yes you expect your water company to not be serving you the above contaminants in your drinking water but there’s no way to really know, including what happens between their water plant and your home.

Plus of course chloramine is much more durable than chlorine, doesn’t just passively off gas and you need chloramine-rated carbon filters to remove it.

So I’d recommend C/RO/DI (all 3) water for peace of mind even with low TDS water. Just be happy your filters last longer.
 
Also keep in mind TDS measured by conductivity doesn’t measure everything in the water, only dissolved ions. So things that aren’t ionic don’t register, like pesticides, petroleum products, pharmaceuticals, PFAS, bacteria, viruses, etc.

And some contaminants are dangerous at very low levels. 1 ppm of NaCl is completely fine. 1 ppm of lead, copper, arsenic, etc isn’t.

Yes you expect your water company to not be serving you the above contaminants in your drinking water but there’s no way to really know, including what happens between their water plant and your home.

Plus of course chloramine is much more durable than chlorine, doesn’t just passively off gas and you need chloramine-rated carbon filters to remove it.

So I’d recommend C/RO/DI (all 3) water for peace of mind even with low TDS water. Just be happy your filters last longer.
Follow up question: Do they really last longer though with all the unknown aspects you mention? I still replace mine relatively frequently which might not be needed but your response rather confirms that I want to continue doing that.
 
Follow up question: Do they really last longer though with all the unknown aspects you mention? I still replace mine relatively frequently which might not be needed but your response rather confirms that I want to continue doing that.
It depends on how you decide when to change filters. If you change them every x months or x gallons, then maybe not.

I change the prefilter, the older of the 2 carbon filters, and the older of the 2 DI resin mixed bed filters when the DI resin in that filter is mostly used up. When I do the change, I move the remaining carbon and DI filters up in the line and put the new ones downstream. I’m pretty sure this means I’m changing out the non-DI filters a little more than needed, but I can’t tell when to change them otherwise, and this seems to work well.
 
It depends on how you decide when to change filters. If you change them every x months or x gallons, then maybe not.

I change the prefilter, the older of the 2 carbon filters, and the older of the 2 DI resin mixed bed filters when the DI resin in that filter is mostly used up. When I do the change, I move the remaining carbon and DI filters up in the line and put the new ones downstream. I’m pretty sure this means I’m changing out the non-DI filters a little more than needed, but I can’t tell when to change them otherwise, and this seems to work well.
I will probably need to look into this more. The Fauna Marin ICP Total test measures RODI water quality and it has not detected anything in the past 4 or more tests, but I am not doing it as sophisticated as you are, so I wonder if there is room for improvement.

My schedule looks like this:

DI resin replaced every 12 weeks
RO membrance replaced every 52 weeks
Sediment and Carbon plus replaced every 20 weeks

I believe this was determined based on the manufacturer recommendation plus some buffer since I do not know the amount of water this is producing.
 
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