Water Question

I searched the board for this, but I didnt see exactly what I was looking for so I figured I would ask on here...

How big of a water change should I do after a tank is done cycling?

Can I use tap water for the cycle and then change it out for RO/DI water after the cycle?

The reason I ask is I would like to get water into the tank and make sure the filtering and everything is working soon and I dont have the money for a RO/DI unit quite yet and I dont have the space nor containers for 55+ gallons of store made water.

Suggestions?

 

You could use tap water (if it was dechlorinated/dechloraminated with an agent such as Seachem Prime). But it may lead to algae problems down the road due to phosphate and silicate content that tap water has (that RO/DI water does not have).

If you did use tap water for your initial cycle, you would want to do some fairly aggressive water changes once the cycle was finished to try to rid your system of as much of these chemicals as possible. I'd personally do several 30% water changes over a few weeks. Even with this, you may find some fairly nasty algae outbreaks once the cycle is done.

Of course, the alternative is to wait until you have RO/DI water, or to purchase distilled water or RO water from your LFS.

 

20-40%, if you do use tap to cycle your tank I would do a 40%. It will be a good start to getting the tap water out of there.

You should be fine cycling on de-chlorinated tap water. The algae that comes during the cycle will consume all the nasties from the tap water.

 

Thats what I kind of thought...

Since I hate algae with every bone in my body (the 'bad' hair algae, not the pretty coralline algae) I think I will just buy the water for the cycle and then get an RO/DI unit for any water changes and for any additional water needs(evaporation, my cat fell in the sump, etc)

Thanks for the quick replies.

 

good plan. watch that cat. ;D

 

Never never ever use tap water, did I say never?
Start it right from the begining and you never have that nagging question in the back of your mind if a problem was water related or not.
Star with RO/DI and stick with it. Many contaminants are cumulative meaning once there, no amount of water changes will ever remove it all.

Algae does not remove nasties as you call them. True phosphates and nitrates feed algae but what about copper, arsenic, silicates etc. Its best to never add them to begin with.

 

I used tap water, dechlorinated obv, for 6 months on my last saltwater fish tank and all the fish were fine. I would never advise tap for a reef or ever FOWLR but for a FO it worked out great.

 

Why should fish get any less water quality than rock or corals? Doesn't make sense to me, they are all living?

 

Yes and the problems that come with tap water don't care whats in your tank. They just happen.