TDS of 124 in mixing water

Dallascowboys16 · Jul 14, 2020

Recently I realized that I have not checked my RO system’s tds reading in quite some time (stupid I know). I checked and I was unpleasantly surprised with a 124 TDS reading. This is the water I have been mixing my saltwater with. I have had a very strange hair algae bloom that came out of no where a few months ago that I’m struggling to control. What are the odds that this can be attributed to the TDS in the RO I use to mix water and top off? I’ve heard a lot of conflicting information on tds which usually boils down to “it depends on what elements are making up the 124 tds”. 124 Out of the RO unit seems high enough to cause issues regardless of what elements are present. I just wanted to get some opinions on how people feel high TDS source water affects coral health. Thanks for releasing and I look forward to hearing some opinions.

shwareefer · Jul 14, 2020

Are you letting it run before you collect water? That looks like a "creep" number, if not your membrane is toast.

Yes, I would say it's connected to your algae.

cmoore806 · Jul 14, 2020

How old was the membrane when the algae bloom started?

Are you on city or well water?

Dkeller_nc · Jul 14, 2020

The answer is, as you stated, "it depends". 124 ppm of copper, of course, would kill everything in the tank. Fortunately, that's unlikely. However, if you're on municipal tap water, one of the chemicals some cities add to the drinking water as a corrosion inhibitor is phosphate. The concentration wouldn't be very high, but might be enough to "fertilize" your tank. Also, if your system hasn't been maintained, it's probable that the ammonia component of the chloramine that most municipalities put in drinking water to prevent microbial growth is getting through, and typically that would be around 2 ppm (if it's all getting through).

While any established tank would very quickly convert that ammonia to nitrate in the amounts that would be reasonably added through top-off and/or water changes, that would still represent an extra nutrient input that most aquarists wouldn't want.

Having said all of that, food inputs generally far outstrip nutrient input from impure top-off and salt mix water, so the bigger concern is the (potential) accumulation of heavy metals in the tank over time.

Jacked Reefer · Jul 14, 2020

I live in Arkansas and some people around here have very successful reefs straight from the tap because our tds is around 110. It really is all about composition, the issue is it can contain copper, iron, and other harmful metals leeched from the pipes. As well as nitrates and phosphates. Test all your Parma’s in the barrel. But I personally would 100 percent change out the filters just in case

Graffiti Spot · Jul 15, 2020

Did you take the tds reading from your storage tank or from an in-line meter on your ro filter?

chipmunkofdoom2 · Jul 15, 2020

Dallascowboys16 said:
I just wanted to get some opinions on how people feel high TDS source water affects coral health. Thanks for releasing and I look forward to hearing some opinions.

This is not a worthwhile question to ponder. None of the anecdotes about using tap water acknowledge or account for context. Some people brag about how they use unfiltered tap water and have a great tank. Some people accidentally use tap instead of RO for a single water change and notice problems immediately.

Because of how different tap water quality can be it doesn't really matter if other people have success with tap water in their tanks. Your tap water is likely going to be completely different from theirs. Even homes on the exact same street can have significantly different water quality depending on the piping used in and between the houses.

Water authorities also have complete control over the water source and purification methods. Most can change both at any time without notifying citizens. Your tap water may be "safe" today, but there's no guarantee it'll be the same next month or next year. The people in Flint, MI had safe drinking water every single day, until one day, they didn't.

People these days are paying thousands of dollars for sleek AIOs, expensive pumps and cutting edge LED fixtures. Paying $200 for an RO unit and a dollar or so a month for the water to run it is cheap reef tank insurance. You just have to keep an eye on the policy and pay the premium every year or so (changing the filters).

Dallascowboys16 · Jul 15, 2020

chipmunkofdoom2 said:
This is not a worthwhile question to ponder. None of the anecdotes about using tap water acknowledge or account for context. Some people brag about how they use unfiltered tap water and have a great tank. Some people accidentally use tap instead of RO for a single water change and notice problems immediately.

Because of how different tap water quality can be it doesn't really matter if other people have success with tap water in their tanks. Your tap water is likely going to be completely different from theirs. Even homes on the exact same street can have significantly different water quality depending on the piping used in and between the houses.

Water authorities also have complete control over the water source and purification methods. Most can change both at any time without notifying citizens. Your tap water may be "safe" today, but there's no guarantee it'll be the same next month or next year. The people in Flint, MI had safe drinking water every single day, until one day, they didn't.

People these days are paying thousands of dollars for sleek AIOs, expensive pumps and cutting edge LED fixtures. Paying $200 for an RO unit and a dollar or so a month for the water to run it is cheap reef tank insurance. You just have to keep an eye on the policy and pay the premium every year or so (changing the filters).

That's the conclusion I have come to after reading all of these posts. I'm kicking myself for letting this happen and not realizing it earlier because I have a feeling it has contributed to some recent struggles I have had with the tank. The tap in my area is notoriously bad and I have a feeling that if I look at the report from the local water authorities there will be heavy metals present. Straight out of the tap our TDS is 1200 ppm which is not even in the "safe" drinking range according to most water treatment companies. I just installed a DI filter and changed ro filters and am now getting 0 TDS after the DI unit. Hopefully I see some positive results in a month or two after getting better water. I would be interested to do an ICP test on my tap to see exactly what is in there...