Water changes

[ND120883]

I have a 40-ish gallon saltwater tank. I'm about a week into cycling (that's when I obtained my LR and fishies). What kind of water change frequency and amounts am I looking at?

Also, what is the best way to do these water changes? So far I've been getting ready-to-go saltwater from a local aquarium shop.

[Lady Hobbs]

A test kit will let you know when and how much water needs changing. Higher ammonia and/or nitrites will dictate larger water changes. Smaller amounts will tell you that 20-30 percent are probably fine for now.

[ND120883]

Ya that 20-30% water change, should I just do that every now and then just for the hell of it regardless of test results? Guess that's what I was getting at. Right now my ammonia's sitting at a fairly low level (0.2) so I think I'm okay for now.

[Lady Hobbs]

Actually, changing water will not be for the hell of it but for saving the fishes life. :) Where your levels are right now will be OK but if your ammonia starts to get over .50 you need to start doing some water changes. When it gets around 1.00, large water changes of maybe 50%. You should be seeing nitrites by now. Water changes will also need to be done when the nitrites start climbing, as well.

Be aware that some fish can not tolerate any ammonia or nitrite sprikes at all and losing some of them will have to be expected unfortunately.

[ND120883]

Yes, therefore why there will only be damsels until my tank cycles and all these levels of ammonia and whatnot level out. Thx hobbs!

[Chrona]

If you are using a lot of live rock (1+ lb per gallon) and have a low bioload, then most people seem to recommend smaller, more frequent water changes for saltwater tanks, like 10-15% weekly, as they become mainly to replenish trace elements since LR removes nitrates. I would ask some of the SW people around here though.

Also, if you are purchasing LR that is not 100% cured (for at least several weeks), then just put the LR in and the tank will cycle itself from the debris on it. Putting uncured LR and fish in a tank = dead fish.

[Fishguy2727]

What fish are in there now?

How much live rock?

[Chrona]

What fish are in there now?

How much live rock?

WHOA, FISHGUY, ;)

[Lady Hobbs]

Reptileguy now in cognito. LOL

[ND120883]

4 damsels, 20lbs of LR, thinking about getting a few shrimp to boot.


PS. Define "cured" vs "uncured" please.

[Fishguy2727]

What species of damsels?

Cured means that everything that died during shipping has been allowed to rot away. This can start a cycle, cycling the tank for you. But if there are fish in there it can mean disaster. Some fish shops will sell live rock that they have already cured since they got it.

[ND120883]

Ah. Probably a good thing to ask the guys at the shop next time I go. How long does it take for the LR critters to die off? I'd say it was at least 30 min between leaving the LR tank at the shop to getting into my tank at home.

They are the blue kind with the black dot on top.