Reverse Osmosis Filter

[fishkeeper2]

Can somebody give me a suggestion for a good yet cheapish Reverse Osmosis water filter? I haven't had much luck in my local pet shops!

 

[rabbut]

RO-man would be the best bet. No RO filter will give the stated output for the membrane under usual conditions, so how much water do you need to make? Also, what are you using it for? I presume you know it cannot be used neet

All the best
Rabbut

 

[drobbyb]

You are going to need to add stuff to the RO water before adding it to the tank. It's fine to top up evaporation with straight out of the unit.

 

[fatheadminnow]

You are going to need to add stuff to the RO water before adding it to the tank. It's fine to top up evaporation with straight out of the unit.

You cant use reverse osmosis water for an aquarium? That's what I use, and I have yet to see any nitrite after about 5 weeks of cycling? Would this explain way my tank is not cycling?

 

[Tolak]

A good ro unit will produce water with near zero hardness. Hardness stabilizes pH. You have to add some minerals back in to bring up the hardness a little, or you will experience pH swings.

As Rabbut stated, it can not be used neet. For fresh water aquariums a percentage of tap water is often mixed back in, for salt water marine salt mixes have all the necessary buffers & additives.

Straight ro could be the cause of a slow cycling tank, especially if the pH is very low.

 

[rabbut]

Agreed, A cycle not starting after 5 weeks is not a good sign. If RO has been used neet, I'd put money on your pH having crashed and that beeing the problem

 

[Miss Wiggle]

yeah i agree with the above,

to expand on why it shouldn't be used neat, when you've got fish in the tank they absorb minerals from the water by osmosis, when the water around them has little/no mineral content (as pure RO does) then the fish can't get the minerals that they need.

think of it like existing off a diet of mcdonalds as your only meal, you might be fine for a while but eventually the lack of nutrition will make you unwell.

so you re-mineralise the RO water to stabilise pH and other conditions like that and add the minerals that fish need back into the water.

the important question for me is why are you wanting to use RO, for freshwater it's not often needed so I'm always slightly suspicious when people are using it!