KH & CA in "almost" fish-only tank

[flanque]

Hello,

I've removed my anemone into another tank with MH lighting to see if I can revive him.

I now have just fish, two hermit crabs and some coral that has grown on its own from a pin dot sized starting. The lights are about 12 months old and are just 2x35w fluros... so the lights suck, but this thing growing on my rock seems to thrive.

Oh, I also have corilamorphs, but they show no signs of dying off.. always open and happy.

I think it will still be important, but for an "almost" fish only tank what level of importance would you place on the KH & CA levels? I would assume KH should be maintained just to keep the PH stable, but CA I'm not all that sure.

What do you think?

 

[steve-s]

Ca should still be maintained within NSW for the health of the mobile inverts. If the Ca becomes too low, they can become lethargic and some will perish. Coralline if any will still have a decent draw on the chemistry. It will not be as important as if you have a reef set up but still something that should be monitored and maintained to some degree albeit small.

Most likely if you are doing weekly (I hope) water changes, that should keep everything relatively in line saltmix depending. YOu shouldn't really need to worry about suppliments.

Cheers
Steve

 

[flanque]

Yeah what you're saying is what I assumed but didn't really feel like admitting.

Just on the salt quality... I use ocean water and not treated fresh water (salt + buffers + neutrafiers of toxins, etc), when doing water changes. Top-ups are with treated fresh water (same as above, just no salt)....

Is there a general consensus on if its better to use fresh water then treat it with salt, buffers, etc or just use ocean water?

 

[steve-s]

Is there a general consensus on if its better to use fresh water then treat it with salt, buffers, etc or just use ocean water?

Depends on the purity of the natural seawater you are able to collect and it's relativity to polulated area's. If you can get water you think is sufficiently free of contaminants, no reason not to use it except the possible parasitic/bacterial issues that can come with it.

Cheers
Steve

 

[flanque]

But surely you'd have the same issues in fresh water with bacteria and parasites, or are we assuming that the amonia and chlorine will kill them all?

 

[cmor1701d]

If you start with RO/DI water and add a quality salt mix you are not taking a risk of adding detrimental parasites or bacteria. Actual seawater most likely contains a good quantity of bacteria and some parasites. Look at a sample of each under a microscope. You may be surprised.

 

[steve-s]

But surely you'd have the same issues in fresh water with bacteria and parasites, or are we assuming that the amonia and chlorine will kill them all?

Actually most (at least modern) water shed systems use chloramines (combined chlorine and ammonia) which penetrate and kill bacteria much better. It also remains in the water much longer and is effective on a wide range of bacterial/parasitic issues. The only time it becomes less effective is when rains or problems disturb the bottom of the holding area to a great degree releasing a greater number of bacteria.

Chloramines are easily treated with a good water additive, as with the RO, the prefilter will remove a great percentage. With seawater, you don't have this option so the next best recommendation in that regard is to store the water in the dark covered for a few weeks before use. It can then be recirculated with a powerhead and carbon to remove polutants/die off before use. The only problem with that scenario is if nutrient rich, the water will begin to smell foul after a short time.

Cheers
Steve