Cycling Questions

I've done some reading around and I think I have a pretty good idea of what I'm doing, this is just my sanity check.

I bought a set-up from someone on Craigslist for quite the steal. 5 foot 120gal with a 30gal sump, rock (~175 lbs) and sand (4") also included. I'm not sure quite how long it was sitting drained inside his house (likely 4 months or so), but the sand was still damp an inch below the surface. There is no growth on the rock. I cleaned out the tank, rinsed the sand in prepared RO saltwater, scrubed and rinsed the rock in RO saltwater, and put it all back together. Tank was filled with prepared RO saltwater on 3/7. I started my equipment 24 hours later, including the skimmer and the UV sterilizer (with a very low flow rate controled by a ball valve from a "T" on the sump return pump). Each day for the first 7 days I added some "Biozyme" accordingly. Temperature has been held at 76-78F (was more around 78 the first week, brought it down to 76 now in anticipation of the heat the lights will add when they are finally turned on down the road). I tested the water on 3/11 (4 days later) and had:
pH: 7.8
Nitrite: 1.0ppm
Nitrate: 40-50ppm
Ammonia: 0.75ppm
Salinity: 1.030

I did a 50% water change Monday evening (3/15) and I've tested the water the last 2 days (16th and 17th). I now have:
pH: 7.9
Nitrite: 0ppm
Nitrate: 20ppm
Ammonia: 0ppm
Salinity: 1.0215 (intentionally brought it down)

I realize it's unlikely the cycle is already occured (even though from my understanding it is possible). I'm in no hurry and will definitely wait at least 3 more weeks before really coming to that conclusion. pH is a little low and I know that I need some buffer to bring it up a tad. I suppose I'm just wanting someone to look over what I've done and offer and tips/suggestions and/or point out anything I've done wrong and/or need to change. Thanks all.

 

Hello Evolved and welcome to the hobby! For starters you did your water change a little to early. Chances are that you did not allow for enough time for the cycling process to occur and in a sense you will be starting back at square one, especially if you did a 50% change. The problem that you are going to run into is the fact that your rock most like sat dry for the period of four months or what ever. The problem with this is that you are going to have to re-cure the rock in salt water, which is a procees that can take quite some time and be quite smelly. If you started the process with fully cured live rock and with live sand and all that jazz I would say that you would be set for some testers ie damsels in about 3-4 weeks. However, given the fact that you are going to need to cure your rock and such I would say the process will take about a month to month and a half or possibly longer. You are not going to want to do any sort of water change for at least that long. I have barely scratched the surface on cycling your tank, but bee sure to look up poper ways to cycle a marine tank and curing live rock online. You should be able to find all the info that you are going to need.

 

Let the tank run for eight weeks without the skimmer, so the bacteria can build up.

 

Welcome to the forum!

Are you planning on building a reef system, or a fish only tank? If you're going to add corals, you might want to bump up your specific gravity to the 1.024-1.026 range.

Also, is "Biozyme" a product that is meant to seed your tank with beneficial bacteria? If so, running your UV sterilizer is just killing it off while it is in the water column. Personally, I don't think that those products are needed anyway, the bacteria is everywhere.... it's just a matter of giving it nutrients to grow. However, if you prefer to use it, just be aware that running your UV at the same time is killing off at least some of what you are adding.

As was mentioned, turn off your skimmer too.... it's pulling out nutrients from the tank that the bacteria use to grow.

Being patient is key, even though we all have the natural urge to stock the tank quickly. I kind of cheated in that I went on vacation for two weeks after I set up my tank, so I wasn't tempted to tinker with it at all. ;-)

 

I commend you for your patience. Here is my mini essay;
Tank cycling:
There are some who would tell you that once "the numbers" are all good the cycle is over and you are ready to go, I am not one of those. What many beginner (even some advanced) aquarium keepers are not (fully) aware of is that the full cycle takes at least 6-8 months. The reason being, mainly, is this is the time required to fully cultivate a total beneficial bacterial base and achieve a saturation of such. Also, allowing the tank to "season" and go through the inevitable mini-cycles and diatom blooms and get fully established is the key to a healthy and stable tank in the future. You could have one fish after about the 6 week mark, let the tank get established by light feeding and going through a moderate light cycle (6-8 hours) for the next 3 weeks.At the 2 month mark, A 25% water change of the "total"water volume is in order. After that, add a few clean up critters (crabs and/or snails) and allow the tank to "catch up" to the added load (you may at this time add some live bacteria to help in this process) and give it another 2 weeks doing all your tests on a regular (weekly) basis and determine if the tank is stable. Water changes of 30% should be carried out once a month to once every 5-6 weeks. Coral should not be introduced (even soft) until the tank is around 3-4 months old. Too many beginners don't exercise the proper patience and discipline at this early stage of getting their tank going only to have problems and head aches down the road. Once the tank has gone through this full cycle period and the tank is stable, then and only then, should you add more difficult coral like hard coral. I always employed a bit of advice I got when I was starting out to add bacteria after each water change for the first and subsequent next 4-5 changes. After the 4th water change then and only then add to the tank and minimally at that.
Another good tactic I learned is to add (whatever you are adding) a couple days after a water change. This gives the new creature fresh minerals and trace elements and a good 3-4 weeks (I adhere to 4-5 week intervals between changes) to adjust to the new water parameters, light, temp etc. before disrupting the tank for the next water change.
I hope this helps.

 

Thank you everyone very much. These are the types of things I needed to hear. I knew my sterilizer should probably be off, but I was just afraid of algae. I kept finding conflicting info on whether the skimmer should be on or off, so off it goes. There's lots of mis-information out there, and about half the things I've read say to do water changes weekly during the curing phase, which didn't stand to reason to me. So thanks for straightening that out too. As I said, I'm not in a hurry and would rather do this right the first time.

As for my plans, initially I will only be adding fish, but my stock list only has reef-safe fish. I'm sure I will move towards a reef tank in the future, so I want to leave myself that option and make it a seamless transition. It seems this is really the proper/preferred slow progression anyways. I have proper lighting already too (3 250W metal halides, 4 96W PCs, and some moonlights).

 

You are more than welcome..........

 

If you get an algae bloom (green water, not just green algae on the glass and rocks), run your UV until the water clears. You still have to remove the excess phosphates from the tank though, or another form of algae will just use them.

UV sterilizers only treat things that are in the water column. There's some common misconceptions that they will harm beneficial bacteria on your LR, or help with non water borne algae.

You'll find differing opinions on nearly everything as you read posts, so don't let it confuse you too much. If you don't believe me, just create a post asking if you should rinse your sand, or what the ideal dKH is. LOL

Personally, I see adding bacteria to the tank as a bit of a waste of money. The bacteria is everywhere on the planet. Add the nutrients it needs, and away you go! It's probably one of the only things in this hobby that is free! ;-)

Is it harmful to add bacteria? Not in my opinion. It's not my money you're spending either. LOL

While you're going slow starting up your tank, just take the time to research all of these issues, and come to your own conclusions.