A Cycling Question

[Cliff]

I’m going to be picking up some live rock to start the cycle in my tank this weekend. I’ve filled the tank with salt water using a really good quality salt and RO water. Salinity is between 1.023 and 1.024, nitrate nitrite ammonia and phosphates are all at 0, and the PH is at 8.2. I’ve got all the equipment running and everything looks like it’s good to go. My goal is to have this tank set-up and running for a few months as a FOWLR tank and slowly add the corals making it a reef tank once I up-grade my lighting to a better quality light that will better support corals.

But I do have a question about cycling my tank

I have a 90 gallon tank with a 30 gallon sump. I’ve already got approx 80 lbs of dry rock in the tank and I will be adding between 20 to 30 lbs of live uncured rock to cycle. The rock will be going in my main tank as there is no room in my sump for any rock. After reading the info on this site about cycling I was not going to have any lights on the tank until after the cycle was done and I had some fish or CUC in there. I don’t want to have to deal with more algae than absolutely necessary as this is my first salt water tank and I’ll likely be making a few mistakes along the way as I learn.

But what if the uncured live rock has some coral on it ? It seems wasteful to allow it to wither and die if I find some coral on my rock. I found a lot of info and heard a few first hand experiences of having corals survive the ammonia and nitrite spikes of a cycle and then latter thrive once the tank is established.

I do have a two FW light fixtures (each double T5 with 54 watts @ 6700K of light) which I was planning to use once I added my CUC to the tank. If I would use these light fixtures, would this be enough light to keep a small coral from dying off (assuming it were to survive the ammonia and nitrites spike) ? On the other hand, would this be enough light to result in excess alga during the nitrate spike after the cycle?

What would you guys do ?



Myka, if you are ready this, great job on the excellent cycling instructions. That info was a great help for me. The best that I’ve found on any forum out there

[sphelps]

No lights, it's doubtful they'll be anything of interest on the rock and even if there is the cycle will likely kill it anyway.

[jorjef]

Use bulbs of 10-12k or larger, the 6700 only good for freshwater. Just go with reduced time if you spot some corals and hope for the best. I had my lights on 8 hours a day during the cycle with no algea bloom but all my rock was cured.

[Werbo]

Myka has posted a good guide to cooking live rock. "Cooking" means keeping it in the dark for 4-6 weeks at the right temperature, salinity, ect with frequent water changes. It is important to keep the rock in pristine water while it cures so you preserve the good bacteria living in the rock that will become a part of your biological filitration.

Not everyone will agree with me on cooking rock. But IMO it is better to start with fully cured live rock free of unwanted algae than MAYBE save a mystery hitchhiker coral.

Keep and eye on the livestock board. Often people give away good starter corals.

[naesco]

There are two schools of thought on the questions you ask.

My view is that live rock contain many things; Sponges, bacteria, coral and macro algae as well as tonnes of critters that are hiding in the rock. Although not necessary for a fish only set up, a reef tank benefits from LIVE live rock.
There is no point in buying live rock and killing it by cooking it IMO although I fully respect the opinions of those who disagree.

Therefore keep the lights on. Place the live rock so that the coral on the rock is closest to the light. If this coral survives harvesting from the sea, sitting on a dock in the sun and the flight over it will flourish in your tank. If algae starts to become a problem it can be dealt with as long as you do not leave it too long.

I disagree that the critters will die in a cycle. That has not been my experience and I have set up 6 tanks with really live rock. BTW take your time a cherry pick the best live rock. Look for lots of life on it.

You did not mention one important issue. Are you planning to add sand to your tank. If so go for a minimum of 2-3 inches of fine sand. It is harder to add it later.

Remember you should allow your tank to cycle which generally takes about a month before you add any fish. Add one fish per month unless they are really small fish.

The concept of a clean up crew (CUC) is a dated marketing ploy. Simply add a couple of hermit crabs if you like them and ten or so various snails. You can add more delicate stuff later.

Congratulations! You are defineately on the right track.

[Werbo]

"There is no point in buying live rock and killing it by cooking it IMO although I fully respect the opinions of those who disagree."

I disagree. Just so you know you are not "killing" live rock when you leave it in the dark for a period of time. Your goal is to kill unwanted algae. You want to perserve the benifical bacteria in the rock by cycling the rock in pristine water absent of light. Unfortunately other organisms that need light will also perish. Some of these will also come back such as many benificial sponges even after 4 weeks of darkness. Your rock will still be live rock after a prolonged period of darkness.

This hobby has many variables that can lead to long term problems. Uncured live rock can leach nitrates and phosphates for many months and feed algae living on uncured live rock.

[JohnnyReeftank]

I'm in your exact same situation (first SW tank)...just about 6 weeks ahead of ya. I bought my live rock off of kijiji so it was already cured. I had tons of hitchhikers that were both good and bad and even some corals. Everything survived my cycle (except a colt coral) and I even added pure ammonia to give it a kickstart. I did not use lights for 4 weeks and a colony of button polyps (paly's), some sea-mat anemones and a colony of mushrooms managed to tough it out. I didn't really worry about whatever was attached to my live rock because it wasn't part of my grand plan and I figured that if anything managed to survive then I would give it a chance...if not then who cares...I paid for the live rock for its filteration and not for the freebies that came with it.

[sphelps]

Sponges, bacteria, coral and macro algae as well as tonnes of critters

Not to disagree but everything except coral and algae listed will survive without light, in fact they don't need light at all to survive and some do better in total darkness such as sponges. Algae you don't want and coral.... give me a break, even in the slight chance of getting something of interest it won't survive. The pros to no light out way the cons.

[Cliff]

Thanks for all of the replies everyone, this is very helpful.

I’m a little concerned about curing the live rock outside of my tank as I will only have 20 to 30% live rock to cycle with, the remaining 80 lbs is dry (dead) rock. I want a good sized ammonia source to kick-start the cycle. After the cycle is complete, I can do a large (40% +) water change to remove the nitrates and phosphates my skimmer doesn’t remove. This is why I wasn’t planning on cooking / curing the rock before placing it in my main tank.

After reading of the responses, I’m thinking it would be best to cycle with the lights off. After all, good filtration and minimal algae is the goal and ( as others have pointed out), I should not be risking that over a few corals that “might” survive.

It will be a lights off cycle for me. Hopefully anything interesting will survive but I won’t worry about it if it doesn’t

I was planning on adding the sand substraight after I have completed the cycle. Just didn’t want to have to try and clean algae off the substraight should I get some while cycling. But after reading some of the feedback here, I think I’ll add it with the live rock this weekend. I’m hoping the cycle will be finished up in a month, but I will let my test results tell me when that happens. I was going to start off slowly with one or two emerald crabs and some snails, turbo snails I think but I still have to read-up on snails a little more to figure that out. After that I’m going to slowly add some fish. I only want easier / hardier fish such as a faxface, yellow tang, and some type of clown fish. I only have to research there compatibility to make sure. Once I know I successfully keep a FOWLR tank, I will start with some easier / hardier corals, some types of leathers, mushrooms, and zoas. I just need to research and figure out which specific corals I will start with. I planning on doing a lot of this research while the tank was cycling to divert my attention away from a big empty glass box !!!

Thanks everyone.