San Antonio water quality?

[pjku79]

I am new to San Antonio (from MI) and will be getting into reefing again soon. My question is in regards to the water quality and what people have been able to get by with and been successful with here. I am looking at doing some SPS. I have three options and I will order them in my preference (cost obviously). Can you tell me which you have tried and which worked? I don't want any speculation here I want facts. If you haven't done it don't talk about it.

1) Using tap water (edwards aquafer)
2) Using soften tap water
3) Using RO water
4) Using RO/DI water

[Mr Cob]

Welcome to San Antonio.

I have used tap, RO and RO/DI.

I found my best results with RO/DI.

I found micro algae problems when I used tap...been several years though since I used tap.

[ErikH]

I have used tap successfully in a SPS dominant tank, however a wise reefer once told me that it's smarter to have as big a buffer as possible to help eliminate any problems. Metals and other contaminants also make their way into your tank as well. I fairly recently purchased another RO/DI unit, and it's worth it for the peace of mind.

[Big_Pun]

i have used ro/di on my sps system on my g/f softie tank its just prime and tap. But i have a friend with a nice sps tank that just uses tap water and prime or water from those stand alone filter water stands ie:windmill or the ones outside the grocery stores. its up to you, i just play it safe and filter my own water.

[hobogato]

i do not have a water softener.

i used RO/DI on an older tank that was sps dominant at one time. then, on my last tank, which was a mixed reef with a few sps colonies, i used tap water that had been run thru a carbon filter for de-chlorination. it is difficult for me to give data on coral coloration or growth because i also light my tanks with sunlight which can cause just as much variation as water quality.

that is the same thing i am using with my current tank. alkalinity, pH and calcium are high with sa tap water, but nitrites/nitrates have been zero the couple of times i have tested. i have not tested it for anything else.

if i were setting up an sps dominant tank, i would likely return to RO/DI

[alton]

In the 80’s most homes in and around San Antonio, Schertz, and other small towns received most of there water from the aquifer. Today that is not so water comes from Canyon Lake, Gonzales, even little lakes like Dunlop which is just south of New Braunfels. The pipes carrying this water can be PVC to a concrete substitute. In the old days you knew it was hard but at least you knew where it came from?

At my old office located at IH10 and West Avenue, the Nitrates where at 10ppm right out of the tap.

At my home here in East Bexar County I have seen chlorine at 4ppm, water that was hard enough to kill a water heater in 4 years. But today I have a TDS coming in at 80 and my hot water heater that has lasted me 15+ years. Sounds great until sometimes when I take a shower the hot water doesn’t smell very well.

As the aquifer’s and lakes around SA continue to drop the water quality will continue to diminish.

I have used RO water for a long time and will continue. I have too much in my tanks to gamble.

[350gt]

I can't even drink tap water around here anymore. I couldn't imagine putting in my tanks.

Been using the water from the little windmill place since I started and no issues of any kind from it..

[pjku79]

Sounds good. Thanks for all of the input everyone. I was guessing I would have to do RO or RO/DI. What is the windmill stuff? How much do they charge?

[hobogato]

i think it is about $.25 per gallon. for the convenience, and long term cost savings, i would recommend getting your own filter. hauling buckets of water gets old very fast.

[350gt]

i think it is about $.25 per gallon. for the convenience, and long term cost savings, i would recommend getting your own filter. hauling buckets of water gets old very fast.


+2 it does get old, mine is right around the corner and I hate going.

Yes it is $.25 a gallon or $1 for 5..

[justahobby]

Once I started spending at least $5 a week (plus hauling jugs) I quickly realized the savings (financially and emotionally) w/ an rodi filter.

[ramsey]

If you decide to go with RO/DI water and make your own, you should check out buckeyefieldsupply.com. They're a sponsor here and you can get a decent deal on a unit. Great service too.

I've tested nitrates as well and found about 20-30PPM out of the tap.

[pjku79]

How many gallons do you guys usually get out of a RO/DI filter?

[hobogato]

not sure what you are asking, but...

there are different flow rates for filters, from 10 gallons a day up to 200+ gallons a day. the carbon and sediment filters usually last about 4 months before they have to be replaced, but the RO membrane can last up to 5 years. the part that is replaced the most often is the DI resin, but that can be bought in bulk from several of our sponsors including air,water and ice (http://www.airwaterice.com/), buckeye field supply (http://www.buckeyefieldsupply.com/) and aquarium designs (http://www.aquariumdesigns-texas.com/). some of our other sponsors may carry it as well, but i know those three have it.

[pjku79]

Thanks for the info. I guess I'll go that route.

[BuckeyeHydro]

How many gallons do you guys usually get out of a RO/DI filter?

A good rule of thumb is to replace your sediment filter and carbon block after six months. A more precise way to maximize the usable life of these two filters is to use a pressure gauge to identify when pressure reaching the membrane starts to decline. This is your indication one or both of the filters is beginning to clog.

Also be cognizant of the chlorine capacity of the carbon block. A good 0.5 micron carbon block for example will remove 99% of chlorine from 20,000 gallons of tap water presented at 1 gpm. Some original equipment suppliers commonly provide carbon cartridges rated at 2,000 to 6,000 gallons.

Regarding your RO membrane and DI resin, use your TDS meter to measure, record, and track the TDS (expressed in parts per million) in three places:
1. Tap water
2. After the RO but before the DI
3. After the DI.

The TDS in your tap water will likely range from about 50 ppm to upwards of 1000 parts per million (ppm). Common readings are 100 to 400 ppm. So for sake of discussion, let's say your tap water reads 400 ppm. That means that for every million parts of water, you have 400 parts of dissolved solids. How do we go about getting that TDS reading down to somewhere near zero?

If you do some experimenting with your TDS meter, you'll note that your sediment filter and carbon block filter (collectively called “prefilters”) do very little to remove dissolved solids. So with your tap water at 400 ppm, you can measure the water at the “in” port on your RO housing and you'll see it is still approximately 400 ppm.

The RO membrane is really the workhorse of the system. It removes most of the TDS, some membranes to a greater extent than others. For instance, 100 gpd Filmtec membranes have a rejection rate of 90% (i.e., they reject 90% of the dissolved solids in feed water). So the purified water coming from your 100 gpd membrane would be about 40 ppm (a 90% reduction). Filmtec 75 gpd (and below) membranes produce less purified water (aka “permeate”), but have a higher rejection rate (96 to 98%). The life span of a RO membrane is dependent upon how much water you run through it, and how dirty the water is. Membranes can function well for a year, two years, or more. To test the membrane, measure the total dissolved solids (TDS) in the water coming in to the membrane, and in the purified water (permeate) produced by the membrane. Compare that to the membrane’s advertised rejection rate, and to the same reading you recorded when the membrane was new. Membranes also commonly produce less water as their function declines.

After the RO membrane, water will flow to your DI housing. DI resin in good condition will reduce the 40 ppm water down to 0 or 1 ppm. When the DI output starts creeping up from 0 or 1 ppm, you know that your resin needs to be replaced. Sometimes people complain that their DI resin didn't last very long. Often the culprit is a malfunctioning RO membrane sending the DI resin “dirty” water. This will exhaust the resin quicker than would otherwise have been the case. Sometimes the problem is poor quality resin – remember that all resins are not created equal.