biological

[bayside795]

I have had a FOWLR tank going for over a year now. I recently removed a lot of the live rock because I felt the tank was too crowded. I have two questions:

1) will the rock stay alive in a bucket of water ?

2) If it does stay alive can I use it to make biological water? What I was thinking of doing was mixing up my monthly water changes with my salt mix and letting this rock sit in the new water, hoping it will be live water like the kind I buy for $13 a gallon at my LFS.

Sorry if this seems like a silly question, my tank is doing fine but the science behind it is confusing to me. Never was a great science student.

Thank you in advance

 

[LauraCline]

The rock will stay alive in a bucket if it has a powerhead, a heater, and you feed and do water changes just like you would on the tank. You can use it to make water with some bacteria in it but the small amount of bacteria you would get in the water would not be worth the trouble. I surely hope that is a typo and you are not really paying $13 for a gallon. If your LFS is really selling it at that price and/or advertising it as "live water" - run, don't walk away from the place and don't look back. Don't worry about sounding silly, the silly question is the one you never ask. The real deal about the liverock is that besides all the neat hitchers, and microfauna (pods etc.) associated with the rock, there are areas deep inside the rock that contain aerobic and anaerobic bacteria. These nitrifying bacteria are mainly what provide the biological filter that breaks down ammonia, nitrates, and to an extent phosphates. The science is very simple, you are basically trying to cultivate and then maintain enough of these beneficial bacteria to take care of most of the waste products produced by the tank. The rock (and sand) provides a place for these bacteria to reside. This is why there are general recommendations for so many lbs. of LR per gallon rather than everyone just making their water in vats containing rock. You will get much more benefit by having he liverock actually somewhere inline with the tank where your water is continually being filtered through it. If you don't like that way it looks in your display, it can also go into a filter, sump, or refugium. I hope this helps you.

 

[bayside795]

Thank you for your reply, it is greatly appreciated. Yes that was a typo about the water, I pay $13 for 4.5 gallons.

 

[LauraCline]

More than welcome anytime. 13$ for 4.5 gallons is about $2.89 per gallon which is still a little bit expensive. As a comparison, I currently buy RO water at $.30/gallon and mix it with salt mix at home. The last time I bought the 160 gallon bucket of Reef Crystals, it was $40 with tax. This makes my water about $.55/gallon. It will be cheaper still (and cleaner becasue of the DI) when I purchase my new RODI unit this weekend.