• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up

What TDS should I aim for?

Sacha

Sacha

Member
Joined
3 Jan 2014
Messages
992
Location
London
I use RO water, and I remineralise using JBL Aquadur.

I typically remineralise to a KH of 4. After dosing with EI, TDS ends up in the 300s.

Should my TDS be lower? If so, that would mean using less Aquadur, which has two drawbacks. Lower KH means pH swings are more likely, and more acidic water means my Nerite snails will not be happy.

So, what is the lowest "safe" KH for a Co2 enriched tank, and how do I make sure my Nerites stay happy in soft water...
 
I use ro and salty shrimp to 're mineralize.I've stopped ei as its the only way I can keep the tds right for our crs. Also turned co2 off and added an air stone. im now loosing plants and I'm considering a small nano for the crs as I'm not enjoying watching all my hard work floating around on the surface. :) our tds is at 170 today .
 
I used neat ro, and then used tropica ferts, they did a great job of re mineralising. If you're using EI, then in essence you're remineralising twice.
 
Not true...

The fish need Calcium, Magnesium etc for their Osmoregulatory systems to function properly. Calcium especially- this isn't included in EI ferts.

It's very important to remineralise RO water... Ferts alone do not provide the minerals which are vital to the fishes' health.

Some South American species like Discus and Angelfish can get away with being in neat RO, but other species will suffer.

Also without any carbonate in the tank, KH will be zero, which leads to a very unstable environment.

Don't you get mad pH swings, because your KH will be non existent?
 
Ok lol!

Your calcium and mg is in your trace elements.

Have a look at viktor Lantos's scapes, he does the same. Quite a lot of us do...
 
Ok my mistake. but my main concern is how can you keep a tank stable without any Carbonate? With a KH of zero?
 
Also, have any of you kept Nerite snails happy in acidic water for a decent period of time...
 
My kh was a steady 5-6

My tds was around 100

I was keeping quite sensitive chocolate gouramis at the time.
 
How did you get a KH of 5-6 if you weren't remineralising?

Were you adding carbonate somehow?
 
Presumably the calcium carbonate in the ferts and also the rocks in the tank. Seryu stone adds to tds. I did dose the ferts quite heavily in the tanks I used with pure ro.

Have a look through Amanos stuff, he also uses pure ro in his tanks. In his book 'the complete works', it gives you a lowdown on what the stats were in his tanks, and his kh was almost always 3-4. This is with real lean dosing.
 
OK, thanks a lot for your advice.

Really I want my water to be as soft as it can reasonably be.

My concerns are really the health of the nerite snails, because I know they suffer from calcium deficiency in acidic water, and the risk of pH swings. I will have to get hold of that book I think.
 
I didn't have any snails in the tank, so can't comment on that. I'm sure it would have a slight impact on their shells though. I had shrimp in the tank and they were fine.
 
Hi all,
Sacha said:
Ok my mistake. but my main concern is how can you keep a tank stable without any Carbonate? With a KH of zero?
Click to expand...
You can ignore pH in very soft water, pH is the ratio of acids and bases, and tells us nothing about amounts. Because you have very few bases (H+ ion acceptors), any small addition of acids (H+ ion donors) will lower the pH. All you have to remember is that large changes in pH reflect small changes in water chemistry.
Sacha said:
Also, have any of you kept Nerite snails happy in acidic water for a decent period of time...
Click to expand...
You can't, this is where both pH and carbonate buffering are important. Because the snail shell is calcium carbonate (in its aragonite form) it is a potential H+ ion acceptor, and if you place a shell into water with lots of H+ ions, they will rapidly erode the shell and kill the Nerite. A few snails are very efficient at extracting both calcium and carbonate from base poor environments, like Malaysian Trumpet Snails, and this allows them to grow in water that is slightly acid and calcium poor, but even in this ase the older whorls of the shell show erosion, and the MTS never grow very large. Red Ramshorn snails can also survive in water that is fairly calcium poor but neutral, as long as the pH doesn't spend too much time below pH7.

I have some tanks (all rain-water but with some carbonate buffering from dust etc) where I can't keep Red Ramshorn or Tadpole snails because the water is just too soft, and one where even added MTS soon dissolve. In all the tanks all the older snail shells are white, and very thin, and I don't have any large old snails. I can't keep any other snails for long, even ones like Assassin snails, which people have successfully kept in soft water set-ups.

cheers Darrel
 
Wow thanks a lot for that response Darrel.

I have nerite snails who have been living in this tank for years now. For at least one year, the pH has been below 7, and the KH below 4.

Are you telling me these snails are suffering in any way? Their shells appear "healthy", although they have changed colour since I got them, from a dark brown, to a light orange colour.

Is there any way I can keep the snails healthy in a Co2- enriched tank?
 
Hi all,
Sacha said:
Are you telling me these snails are suffering in any way? Their shells appear "healthy", although they have changed colour since I got them, from a dark brown, to a light orange colour.
Click to expand...
I'd imagine they are probably all right. The fact that the shell has changed colour maybe because the outer layer are being eroded, if this is the case I'd expect the older whorls to be lightest and the newer shell material around the mouth of the shell to be darkest. If they haven't grown? it maybe that they can't make new shell.
Sacha said:
Is there any way I can keep the snails healthy in a Co2- enriched tank?
Click to expand...
I don't know the answer to this one, but some-one who has a high tech. tank and snails should be able to. When you depress the pH using CO2, you are altering the CO2 ~ HCO3- equilibrium, which gives you the strange situation of having low pH in (potentially) carbonate rich water.

cheers Darrel
 
Actually, I did once have a nerite in ro water, this was c02 enriched. You can see the c02 whiz zing past it.

AwdjLhD.jpg


He looks ok. He did last as well, until he made an escape from an open top tank.
 
That's what I've heard if they don't like it they make for the lounge floor Or walls:D
 
You must log in or register to reply here.
Back
Top