Fighting Our 180 Tds Tap Water

It would seem that South American angelfish prefer a TDS in the 80 - 150 range, or so I've heard. Its better for their livers. I've known for some time, from an API General Hardness test, that our tap water was pretty high. Recently, we decided to quantify this a bit more and fix it. The first thing we did was to buy a TDS meter.

After calibration, I tested our tap water at 180. This wasn't too much of a surprise.

Then, I went around and started testing the tank water on (4) tanks we currently have running. The ranges went from 280 - 370. This was some really upsetting news. I've been doing 20 - 30% water changes on these guys almost daily now, but I'm pressed to get the levels below 240, which is still way too high.

I figured if I could get our tap water down to about 30 or 40 TDS, I'd be fine with that. Then, add some Cichlid Lake Salt and Trace Elements to get the tank TDS around 140.

So, I decided to do this a bit at a time. I just finished hooking up my first (3) stages:

1. 5 Micron Spun Wound Polypropylene Sediment Pentek P5-10
2. 5 Micron Hydronix CB-25-1005 NSF Carbon Block Filter
3. 1 Micron Pentek ChlorPlus 10 Carbon Block Filter

I don't have a reverse osmosis in place yet.

The frustrating thing is that I fully expected that this would have SOME effect on the TDS. It hasn't. In fact, I've dumped about 20 gallons through this so far and my TDS reading isn't budging from 208. I've GAINED 28!

Is this normal that the first few stages before the RO have no effect on TDS?

-Steve

 

Yes, the RO is the part where it removes it.

 

The sediment and carbon filters just clean the water of debris and chlorine before getting to the TFC [ Thin Film Composite] filter [the ro part].
It is the pressure applied [you need good pressure of 40psi.+ preferably over 50psi] that stops the dissolved solids from going through the filter.Osmosis is water reacting to pressure and ony the cleanest water goes through the TFC and rest is wasted which is where you reject the dissolved solids.
When you hit your target you will need to top off with only ro water or you will be slowly increasing the TDS as they do not evaporate like water.

 

Thanks.

I'm going to pick up the RO unit at the end of this week.

 

Nice looking angel in avatar.
I am breeding albino Dantum angles imported from Israel right now .
They just ate a huge hatch .I am working out of town and can't separate the fry due to lack of time to properly raise them for the first 2 weeks.
They are not wild stock and have successfully breed in 230 TDS water [my source is 350+ ].
I just mix my ro and tap to hit target number without adding anything else. Been breeding rams in under 100 TDS water like this for years.
Good luck and keep us posted on breeding.

 

Your so lucky to have a TDS of 180 out of the tap,wish mine was the same, I get around 450 from the tap, once a week I need to produce 100ltr of RO for my shrimp. Very nice Angel

 

I finally hooked up my RO stage yesterday. Its currently reading a TDS of 57. I'm pretty happy with that. I may add the DI at some point ... still undecided.

 

I only use the DI Resin as I need to polish the water to the best quality for my shrimp, if it works for you and you're happy with 57 then that's fine, I don't know what's best for your Angels but I'm sure someone will advise