Cycling a Tank ... A few questions

PaulPerger · Oct 20, 2017

Just as the title says... I am preparing to cycle my first salwater tank and I have a few questions...

Info that might be important:

Display Tank will be between 40 & 75 gallons (I haven't decided which tank I am going to use) with a 40 gallon breeder as the sump, so water volume will be ~60-100 gallons.
I am picking up ~80 pounds of rock today
I plan to have some corals and coral friendly livestock

First, I am wondering how important lights are to the cycling process in a Saltwater tank? Or are they important at all? I am wondering where in the timeline I should plan to buy a light for my tank. Is this something I should plan to do before I start cycling, somewhere during the cycling process or can a light wait until right before I start adding livestock. Can I use just a basic light for the cycling process instead of a light adequate for corals?

Second, Can Lava Rock be used in a Saltwater Aquarium. I have some really nice large pieces that I used in a previous FW tank. I had forgotten I had them, but found them last night and I was thinking they would look very nice in this tank.

Any advice is much appreciated...

DLHDesign · Oct 20, 2017

Greetings!

PaulPerger said:
First, I am wondering how important lights are to the cycling process in a Saltwater tank?

During the initial three phases (ammonia, nitrite, and nitrate cycles), you don't need light. You can have it if you want, but it's not required. During the various algae bloom phases that follow, however, you will need lighting. Generally you will want this lighting to be the same as you will have on your tank once it has everything in it.
See Section 5 here for more info.

I'm not sure about the lava rock, but I likely would not use it. Some lava rock (rhyolite) has relatively high levels of silica compared to reef rock, and if you put this into your tank you would constantly be fighting against diatom outbreaks. Others may have better advice for you here, however - I've never really looked into it...

Ludders · Oct 20, 2017

You can add the lights just before you're ready to start adding live stock.
Have you an idea of what lights you might want?

My advice would be to not be tight with your budget when it comes to lighting. This is an area where you do get what you pay for and more complex corals require decent lights.
Do some research on possible products you have seen.

Your old lava rock will be okay, but I would recommend curing first.

londonloco · Oct 20, 2017

If your starting with live wet rock, I would run lights, if your starting with dry rock, lighting doesn't really matter.

PatW · Oct 20, 2017

You can cycle an aquarium without lights. You just need a source of ammonia, and patience. If you plan to have corals that are photosynthetic, well the corals aren’t, their zooanthellae are, you will need high quality lights and they are not cheap.

I would suggest using only rock that is from reefs, either recent or fossilized, and made of calcium carbonate. Your lava rocks might leach out metals which marine invertebrates have trouble with.

Idoc · Oct 20, 2017

I didn't use any lights during my cycle. Everything I've read said too leave them off during a cycle to minimize the algae growth during the cycle. This gives you a month or so to figure out which lights you want.

I used straight ammonia dosed to 2ppm to cycle my tank. Then kept dosing 2ppm until the tank was able to clear it in 24hrs.

PaulPerger · Oct 20, 2017

Thanks for all the replies! This is pretty much what I figured, but I appreciate the confirmation! As for which light I am going to use, I am not sure yet. That is going to somewhat depend on which tank I decide to use. I am leaning toward my 40 Gallon Bowfront, as I think it is the most attractive tank of the three in consideration.

@Idoc - I have used straight ammonia to do my FW tanks and plan to use it for this one as well. I always dosed my FW tanks to 4 ppm initially, then when it got down to 1, dose it up to 2 ppm, and then wait for zero, dose to 2 ppm wait for zero and keep doing this until 2 ppm went to zero in 24 hours seven days in a row. Once that has happened, I consider it cycled.

Seems like there are mixed opinions about the lava rock. I did some other reading and apparently, it is fully dependent on what type of volcano developed it. Since I don't know that, nor what trace stuff might be in it, I don't think I'll use it. My FW fish love it, so it won't go to waste, I'll just need to set up another tank.

And, I am no longer concerned about possibly needing more rock... I just got home with the rock I bought and there is about 50% more that what I expected! He said it would be about half a 30 gallon tote full, well I brought a 25 gallon tote and I can't put the lid on it! I think there's about 110-120 pounds of rock, not ~80.

So, I guess it's time for me to start a "Build" or "Journal" thread, I officially have made a few purchases and I'll be starting to cure the rock this weekend.