Water Top-off question

[Aquaman99]

When it comes time to top-off the water in my tank due to evaporation, can I use plain old RO/DI water or does it have to be a premix with salt?

i understand that if I am doing a PWC it needs to be mixed with salt...just wasn't sure about topping off the water though.

Thanks

 

[austinsdad]

Never top-off with SW. You'll raise the salinity level. Ya see, when the SW evaporates from your main tank, the salt remains. As you may realize also from this, when you evap too much your salinty readings will go up which is why some purists top-off every day to keep the salinity constant. Salinity up and down so frequently can stress your livestock and cause illness.

 

[Ziggy953]

Depending on the size tank you have you may want to look into an auto-top off system. There are several options available on the market and I always found that having one on my system kept my SG levels nice and constant.

 

[Zer0]

I agree with Ziggy. ATO's are supposed to be great. I'm getting mine from autotopoff.com. Good prices and quality products(from what i've read). And if you have a nano tank.. or just a generally smaller sized tank, salinity levels could swing just by the water level dropping a quarter of an inch. That's why i'm getting mine. Only have a 25G tank, and my water level drops a good inch, inch and a half if i left it the whole day.

 

[Aquaman99]

Can you integrate an ATO unit with a sump?

 

[Zer0]

Yeah. That's probably the easiest place to put one actually.

 

[Ziggy953]

I agree with Zer0, the sump is a great place to have the ATO, this keeps your display tank nice and neat looking.

 

[capj64]

tagging this for future use - Auto Top Off

 

[Zer0]

Yeah, it's a very good idea. It really does help to keep stable SG levels which is a big plus, especially if you have very sensitive coral or inverts like sea stars.

 

[Ziggy953]

Which ever ATO you decide to go with make sure that you check that it is functioning properly on a regular basis. It is always a good idea to have redundant shut-off systems in place. Adding too much fresh water is equally as bad as not keeping up with evaporation.