I am killing my fish


Reefing newb
I purchased an 8 gallon Biocube about 6 weeks ago. The owner of the local fish store sold me some live rock, fine sand, saltwater, Kordon NovAqua Plus Water Conditioner and AmQuel Plus Ammonia Detoxifier and Start Smart. He told me to come back in a week and have my water tested.

I came back in a week and he said my water was perfect. He sold me some snails, crabs, cleaner shrimp, clown fish, lawnmower blennie, longnose hawkfish and a couple of corrals that I can't identify. A week later he sold me a sea anenome (he said the clown fish would want to host it) and another coral.

Everything was great for the first month, 20-30% weekly water changes, fish and corral seemed happy. I bought a testing kit and started testing myself. Then the clown fish started acting strange. He was normally very active but now he was just swimming near the sand in one spot. The blennie was also less active. The clownfish started looking a little ragged and his gills seemed red. I told the salesman and he told me that clownfish will pick a spot and stay there. I stopped worrying and went about my business.

A couple of days later the clownfish and blennie both died within hours of each other. I did a 30% water change. The hawkfish seemed ok for about a week and now he is acting funny. Same thing, staying near the bottom on the sand, gills seem red and breathing seems more labored.

I can't figure out what I'm doing wrong. The water seems ok. Ammonia zero, Nitrites zero, PH 78-84, Nitrates have always been around 10-20 ppm have never gotten them lower than that (usually near the 20). Any suggestions for a beginner? What is going on?
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there are so many kinds of anemones( some more toxic than others) if you could post a pic we could ID it and , my guess ouyt the blue is that since the tank is so new the anemone is probable dying and releasing toxins into the water , basically poisining your livestock. anemones have no bussiness in brand new tanks under (some people say a year) they need pristine water conditions and very high lighting. also not all clowns need anemones and its not always a sure thing they will host a nem, mine hosts my brain coral and is extremely overprotective of me getting near it

10-20 trates are ok for fish but not ok for some corals and anemones.

also just a note 30% water changes are in my opinion a bit to much 10% water changes should be suffice in a small tank . i have a 10gallon and i only do 10% weekly

more people will come in and shine some light on your case

btw welcome to the site and hope we can help :D

also dont buy things just cause your LFS is telling you to... do a little research , i have my Droid in hand everytime i go into a store internet at my finhgertips is a big life saver , even if i dont always do what is adviced atleast i know what im getting into.
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First off, Welcome to the site!

Unfortunately, you had a few things working against you from the start. While a week may be enough for a tank to cycle, it is way too quick for 3 fish to be added all at once to a tank. Also, 3 fish are way too many for an 8 gallon tank, in a tank that size you're limited to one small fish.

A tank only a few weeks old is way too young for an anemone. In the wild, clowns need anemones for protection but, in our tanks they definitely don't require them. I know your ammonia tested zero but, most of the time red gills are a sign of ammonia burn.

My suggestion for you would be to heed your LFS advice with caution. Think about this, they sold you all this stuff and now that it died you will go back there seeking their advice and purchasing more livestock from them. My suggestion for a beginner would be to seek multiple sources before making any decisions regarding your tank, ask your store, search google, and ask multiple forums. That way you can get multiple POVs and experiences.
Thanks for the response guys. I have to admit I'm feeling a little overwhelmed with the whole thing and I may have been suckered by the store owner. Anyways I still love the thing and want to fix it so I appreciate your help.

Should I yank the sea anenome out of there? I'll take a picture of the fish, sea anenome and tank first thing tomorrow morning.
If the anenome is still doing fine and so is the inverts, than let them work a little bit and let the mature a little bit more. Another thing even though your numbers may seem fine, the can spike up in a real hurry, I see you have an Ammo de-tox, but there is also a nitrite and nitrate de-tox, up here I use PRIME, may be worth looking into, I have fallen into the exact same boat, and have lost the same fish you have, trust me and the rest, that will tell you to slow down and enjoy your tank as you build it.

P.s. Our tanks are considered Nano-tanks believe me they are very high maintenance

Ejoy the ride my friend
Welcome to the site...glad to have you aboard. I'm sorry to hear about your troubles, but I agree, the lfs is getting over on you. Don't get discouraged, and take your time...patience is your best friend in this hobby. :)
Hello and Welcome!

Im sorry you have had such a rough start. I personally would suggest removing everything thing still alive and start off on the right foot.

Also each fish need a certain sized tank and the 8 gals is much too small for the hawkfish and blenny, but a clown could be ok in there

Here are some articles that will help you
Thanks again for all your help, what a great community. I noticed my hermit crabs seem to be slowing down and they are clumping together. And one of the corals is not "blooming" anymore. I just pulled out the sea anenome and I'm heading over to the fish store to get water for a water change. I am going to try to save the little longnose.
Welcome! Search the site for subjects you might be interested in learning more about before just following the advice of a LFS owner who needs to sell to make his income! Everyone has your back above with the recommendations which I too think they are right on! Glad to have you on board supporting the hobby.
Hi, welcome to the site.

Two things.

1) BL! is right on point with his feed back.
2) Find a new LFS, that owner has his head wedged up his ass.

Keep asking questions here. The folks on this site contain alot of knowledge and love to help out. You'll be okay.
Thanks again for all your help, what a great community. I noticed my hermit crabs seem to be slowing down and they are clumping together. And one of the corals is not "blooming" anymore. I just pulled out the sea anenome and I'm heading over to the fish store to get water for a water change. I am going to try to save the little longnose.
Something that was recently brought up in another forum I am on that you might want to take into consideration is the quality of the water that you are getting from your LFS. Making a long story short a member bought what was being advertised as Ro/Di water, tested it on the fly and EVERYTHING in it was so far out of wack he cant put it in his tank. He sold you the water originally, and told you that your levels were fine...I would question that a bit if I were you personally. I have learned just "taking their word" for it isnt the best route to take.
He clearly is not selling you things you need for your tank....I am sure others have touched on this but a lawnmower blennie can quickly run out of food if you dont have the algae there to support it and the longnose hawkfish requires a tank of at least 30 gallons. Im not going to claim I am more responsible then you with the anemone situation as I have two and my tank is only 3 months old, however I know that my 30 gallon is a lot of work and maintenance to keep all the levels perfect for them. Not saying you dont, but I think your LFS set you up for failure here. The best advice I can personally give you is to look at your tank, vision what you would like for your nano to be and work on it from there. Realistically you should only have one fish in there, so I would get something beautiful to watch, like a firefish. They have the tendency to jump though so I would definitely put a lid on the tank. After that get some fun inverts!!! Feather dusters add beautiful color and movement, some sexy shrimp would be fun to watch....from there add coral!!! You can have an amazing nano, just do your research before hand. Get on sites like Aquarium Fish: Tropical Freshwater Fish and Saltwater Fish for Home Aquariums find what you like, learn about it and have fun!!! Im certainly not the most advances aquarist, or the most experienced however in three months I have not had one issue with my tank and I credit that to diligence and knowledge.
I ditched the sea anenome, did a water change, stopped dumping chemicals in the tank and I am actively searching for a new LFS. Things are looking up. I think my little fish is even perkier. When I fed him today he gobbled up the food so quickly you'd think I'd never fed him before. Thanks for everybody's input, it is much appreciated!
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glad to see things are getting better. I'll probably get yelled at by other members but the hawk should be fine as long as you don't add any more fish.
great to see your tank doing good, best of luck and keep us posted :D
your zoas are looking nice :D ( i need to get me some lol

Welcome to the nano tank club :D