What happens when the lights go out??

First off, your tank is still cycling and I would wait for about 4 months to add anything else. In the mean time, work on keeping all of your parameters in their proper ranges and steady. Here is my mini essay on cycling;
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. When using live rock and/or sand, the die off will start the cycle. 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.
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.

 

If it is an O2 problem, I would recommend swapping out the glass top with an eggcrate (also called light defuser @ hardware stores).

I had the same issue, but I caught it early. I was a little hesitant to switch to eggcrate, but was VERY happy I did.

I think with black eggcrate, properly cut (I used wiresnips... worked like a charm!), the top looks better than glass, and still provides protection.

 

Looks like O2 combined with still cycling is the issue.

What are you nitrites? Nitrates? Ammonia? Those values will tell you whether or not you have completed the primary cycle.

Also looks like you are stocking too fast.

That many fish in a two month old tank is too many too fast IMO.

Also adding surface agitation with one of your PH's will assist in gas exchange.

I would also surely remove the top - having no sump or skimmer, the closed top is more likely to be an issue.

Hopefully this helps!

And I agree with unclejed - you are going to need to wait several more months before adding anything else.

The nem likely died because the tank was nowhere near mature enough to handle that fragile of an animal. Also, what is the lighting you have on the tank? Nem's require intense lighting.

 

Also I notice you have a landmower blenny and a SS Star listed in your sig.

So does that mean you actually tried 5 fish in your tank within 2 months? That's quite a lot of fish in such a small tank in such a short time. I would not stock more than 1 fish per month at most. When they are dying - that means something is quite wrong and adding more fish to "try them out" will only prolong and compound the problem.

Looks like now you should be getting a full run of test kits and focusing on sticking to a workable maintenance routine of water changes - especially if you are running skimmerless - you will want at least 15-20% per week of a water change. Be sure to mix/aerate/heat the new saltwater before adding.

 

I am not intending on coming down on you but you have asked for help so . . . .

The other thing I noticed is the SS Star - they generally need excessively large tanks which have been established for a year or more. It will likely slowly whither and starve to death in your tank - after some time you might be able to try one - but at this point it is more humane to return it to where you got it or pass it on to someone who can more aptly house one at the moment.

 

My tank is almost two months old, I started with the chromis and just recently added to pair of clowns. I dont believe I stocked to fast, but everyone has a different opinion. Some say a month some say 8 months it all depends.

Im going to my lfs tomorrow and purchasing a skimmer. It would be easier then removing the hood and buying another powerhead. Hopefully it helps

As far as lighting goes I have T5's

 

I think adding a skimmer is the right move. However, you should shop around online and spend your money on the right one the first time around. Reef octopus makes a great HOB skimmer. I'm not sure what your lfs has to offer but typically you will be much better off doing some research and buying online. Search HOB skimmers on 3reef and you should find what you're looking for in your price range.
Good luck and keep us informed. -JW

 

take your time and really research the skimmer. all skimmers are not created equal. some just run better than others, with less issues. and putting another power head in would be easier. but i do think you will want a skimmer.

 

It's really not a matter of opinion, it's a matter of whether your tank contains enough beneficial bacteria to handle the bioload. If you keep adding fish this early in the life of the tank and they keep dying, the tank cannot support them. If it can't support more than 2 fish, it can't support a nem at this time.

We have a 55 with a 20+ gallon sump. Our ammonia was off the chart when we cycled, and it took well over a month for the cycle to complete. We didn't add anything until the cycle completed, then just added a very small clean up crew. After the 3rd month we added 4 fish all at once, which was scary but since our ammonia was so high to begin with, we easily had enough bacteria to handle 4 fish at once because we waited. We didn't have an ammonia spike at all after adding the fish.