ok they do need your mains to above a certian psi (cant remember of the top of my head what)like mine was low so i put a pump on to it to increse the product water.
if you have a look to see if it has got membrane flush on the front as this will help.


Lee

yes that is what I meant - 45 psi? couldn't remember the term!

ok, just got my TDS meter, these are approximate readings as they vary a few points each time I test

Tap : 350
RO : 7
RO with minerals ready for use : 210
Tank : 430 !
LFS : 530

Should I be worried by any of that? Like why the water used for my tank is 210 and then after its been in the tank its 430? Does this mean something is getting into the water from the substrate, plants or food?

///ps// should probably have mentioned I am keeping tropicals, not marine!

your ro reading is a lot better than mine.mine is 35.my tap water is around 62 but i assume that is because i'm in a soft water area.just tested my discus tank and i'm getting a reading of 117.at the moment i'm using tap water in my discus tank but i'm planning on using ro water soon

Do you have a flush setting on your unit? I found that my TDS was higher before I flushed he membrane for 20 minutes.

Quote:
that is so not fair mines 330 out of the tap and i bet your ph is low out of the tap.


Eagle what minerals you putting in your ro water and how often do you do water changes.

when you do your next couple of water changes try using less minerals and se if it drops.

Lee

Quote:
I'm doing roughly 10% water changes, about 15-25l per week. I'm getting about 15L evaporation a week too which is topped up daily. I'm often(but not always) using pure RO to top up as the minerals are not evaporated with the water.

I'm adding "Tropic Marin(r) Re-Mineral Tropic" as this is the only thing on sale in the lfs. Happy to change when this one runs out in a few weeks.

no i don't have a flush setting on my ro unit.i will run it this weekend and see what reading i get once it has run a while.
i don't add anything to the water aprt from the salt of course.i understood that you don't need to add anything unless it is for freshwater fish