100 gallon FO tank needs help!

doglvr

Member
My daughter started working for a local coffeshop that has a 100 gallon fish only tank. When she told the manager about my reef tank, he asked if I could take a look at their tank because the fish died all the time. I went in this afternoon with test kit & hydrometer on hand. Good timing too because the fish person has been in about 2 hours prior, cleaned algae off the glass and did a 10% water change. This is what I found:
100 gallon plexiglass tank with built in overflow
2 - single 20 watt CL 50/50
Sump w/ bioballs & skimmer (so much salt crud couldn't get more details)
2-3 inches crushed coral bed
several large "decorative" aquarium coral (gets bleached 1 a month by fishperson)
top of tank is completely covered with sheet of plexi & light sit on top of this with holes cut out for them.
Salt - 1.028
PH - 8.2
AM - .25
NI - 0
NA - 200+ (off my chart)
I have not been able to ID all the fish yet but believe:
4 Black & white stripped clowns
1 Triggerfish
1 Spotted Cardinal (know this one for sure)
No inverts, ie snails, crabs, etc.
I have a reef tank & know what this needs, but no experience with a fish only tank. I was told the fishperson does water changed directly from the bathroom sink, adds salt to the sump, cleans the glass & leaves. No hydrometer or testing kits have ever been seen. The managers first task is to get 50 gallons of RO water, 5 gc bucket & a hydrometer! My plan is to get the salt, AM & NA down as quickly as possible. 25% change, wait a couple of days and do another 15-25%, and then 1 more to "fine" tune.
Is the lighting good or bad for FO? What are the water parimeters fish only? Stocking suggestions would be helpful with the fish already in there. The "completely" covered top has me concerned with no room for air-gas exchange.
My thinking is to add some live rock, get a clean-up crew, and then add some more fish. This is a Hawaiian based coffe shop & they want a low maintenance "cool" tank with lots of colorful fish. Maybe I am dreaming, but finding some low light living thing for the clowns to host would be sweet too. It was sad to watch them in the fake stuff & apparently they are very aggressive towards other fish in the tank.
Comments, thoughts, suggestions, help??
 

madman33

Member
first of all throw the hydrometer in the trash...get a more accurate floating one at the least if not a refractometer...also probably would be good to upgrade the lights just so you can see the fish better and if you are planning on adding lr then they definetly need to be upgraded. Also maybe see if you can take the cc out and put in sand. 4 clowns not the best idea and it sounds like they are fighting so i would probably take 2 out. I would upgade lighting add lr and get some low light but colorful corals like zoos and shrooms. Lr will probably help with the agression IMO because it would give the other fish at least a place to hide. If you are going to add a clean up crew and corals though be wary that all triggers arent reef safe? Do you know what kind of a trigger it is? Those would just be the basics IMO(better lighting(if you want the fish to be visible and colorful lol) and get rid of the hydrometer) Then once you get all the levels back to normal possibly slowly start adding Lr little by little so there isnt this giant cycle killing all the rest of the stuff off. Then after you/he is satified with the ammount of lr then add whatever fish... JMO on what i would do...
 

doglvr

Member
I had a feeling the lighting wasn't adequate enough for fish. This 100 gallon has 2 - 20" fixtures which I believe might be t5's. I would guess too that the bulbs have not been changed in 5 years. I am going in tomorrow morning to do the water change, clean up the sump, etc. Bio-balls are they a good or bad thing? The tank is built into a wall, with top, sides & back painted black. Getting in to it will be a nightmare so no changing over from CC to sand! My thinking on live rock was a couple of large pieces that could sit under the lights. I am going to recommend an upgrade. I agree on needing to get 2 of the clowns out. Taking my camera so I can get a positive id on the trigger (if it is one).
Yeah, tomorrow should be fun...cleaning years of salt gunk from the sump and catching 2 clowns in a 100 gallon tank.
 

hagfish

Active Member
I think the main problem is the nitrates. Your RO water changes should help that a lot. If the fish person is getting the new water out of the bathroom sink and that tank has 200+ nitrates I think they need a new fish person.
Is there no LR at all? I would definitely add some. I'd say at least 50 lbs. It can only help.
Take the glass tops out and use eggcrate. It will serve the same purpose, but allow for better O2.
Don't go crazy with the lights. If there is nothing photosynthetic then just get enough to show off the fishes colors. NO lights can typically do this. But if it's just 40 watts of NO, that might not be enough on that tank. If they are t5's then that may enough though.
I would lose the bio balls. They are probably adding to the 'trates.
 

saltn00b

Active Member
they can run FO if they want to, you just need to have filtration else where.
the lighting is fine for FO, but as stated, always will look nicer with something a little brighter. the Trates is the big problem, second is the mixing the salt in the sump, that can be VERY hazardous. so you are taking the right steps with ordering a mixing bucket and many gallons of RO / salt. but get a refracto for sure.
for filtration make sure the skimmer is working, as that is the first line of defense, and make sure the fish person is cleaning and maintaining it.
clean the bio balls as they need this from time to time or the become a nitrate trap / facrory. if you look at the sand bed their is probably bubbles all along the side of the tank, that is anearobic bacteria creating nitrate bubbles (basicall) and that is because A) the substrate is not sand, but CC - replace it. B) the height of the substrate is in no mans land, AND he has no inverts to stir it up, so either go bare bottom, or a very light dusting of LS, only 1/2" deep MAX. i would fill the sump up with LR for extra filtration, check that the person is replacing the media floss paper every week or 2, and doing 20% water changes until it is under control.
as for livestock the trigger will likey harass the clowns to death and they should not be kept together, I have only seen large Maroon or GS Maroon (5" + fat boys) be mean enough to survive an agressive tank (as that is what he has with the trigger). if he wants FO, not aggressive, then take the trigger out (what type is it?) and you can get a nice angel and some nice butterflys (BUT ONLY WHEN EVERYTHING IS normal, acceptable levels for a while). i also agree about the eggcrate top.
 

madman33

Member
also agree with the egg crate but make sure you can find some(its impossible to find where i live) before you throw away the other top. If you cant replace the cc then maybe take some out so its not so deep and get some things to stir it up.
 

doglvr

Member
The store's hired fishperson was not pleased with what I had to say about the tank & the care it has been getting. She told the mgr that she was raising the nitrates to 200+ to kill the algae.
I'll get some pics tomorrow of the tank & fish. So far all the advice is right on to what I was looking at, egg crate, getting the bio balls out & adding LR to the sump.
 

madman33

Member
hmmmmm i dont think ive ever heard of anyone raising the trates that freaking high to kill off algea...actually i dont think ive heard of anyone doing that at all. You really should get something better than a hydrometer though...mine was brand new and .011 off lmao.
 

hagfish

Active Member
Actually, raising the nitrates like that would cause more algae to grow. If it's at all possible I think this store owner needs to get out from under the fish caretaker.
 

doglvr

Member
From all I have read, Nitrates cause algae! I was able to get a better look at the tank, fish & equip. today.
The tank is 1/4" plexiglass, the top is glued on with 3 holes cut out, overflow & 2 20" L retangles that the lights sit over. The top, back and sides are painted black. So there is no switching over to LS/LR or using this tank as a reef. There is no catching anything once it's in that tank without some luck and 2 people with big koi nets
The skimmer is a huge Fathom TF100A. I didn't want to mess with it until I research how it works, but it is turned down and not "skimming." Taking off the cup will be a pain, has about 20 screws to play with. Probably the reason it's set to not skim. I am going to recommend a new one that is easier to clean & work with. It appears that the top to the bio-balls is also glued, so I won't be able to clean them or switch over to LR.
The fish I got totally wrong! There are four huge black & white stripped damsels, 1 spotted cardinal, and 1 extremely huge maroon & gold stripped clown. It was hiding in the back so I didn't see all of it before, knew enough that it wasn't a tang or angel, so just assumed it was a trigger of some sort, live & learn! It's actually more of a dark brown with bright yellow stripes, than maroon & gold. So, sadly there is no adding any more fish to this tank without taking the "5" out. The damsels take one side and the clown has the other.
 

f14peter

Member
doglvr said:
The store's hired fishperson was not pleased with what I had to say about the tank & the care it has been getting. She told the mgr that she was raising the nitrates to 200+ to kill the algae.
When I read your first post, the first thing that popped into my mind was what was going to be the reaction from the current (and may I presume, soon to be EX) caretaker. I'm still a card carrying FNG, but even I know the current regimen is far from desirable. Of course, having fish die "All the time" would be enough to make someone rethink how their tank is being maintained.
Sounds like you're doing all this gratis (commendable), but if this becomes a regular gig, I think some compensation would be in order . . . I think free turbo-mochas for life at the minimum!
 
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