Fish Only Setup Idea

[fishboytoo]

Hi,

So, it's been 2 months since I started my nano tank and the salt-water bug has infested my veins worse than a bad case of schistosomiasis. Now I'm thinking of converting my 90gal african cichlid tank into a fish only set-up. I am rather bored with the tank as it is now.

My wife is not very happy about this.

I have spent quite a bit on the nano in the last bit and we are probably going to move in a year, so I can see her point of holding off. I probably won't wait though.

I am trying to figure a way to do this on the cheap and am thinking the biggest expense is the live rock at 90+ lbs x$8-9=>$810. The tank right now has close to a 100lbs of tufa rock on a base of granite(CaCO3). If I switch out the silica sand with aragonite and use a little live rock to "seed" it, will the tufa be able to provide biological filtration? I imagine it would be better than nothing. Do you think this would work?

I would use a protein skimmer and of course would add powerheads to provide better flow.

Please let me know what you think.

Chris

 

[xxBarneyxx]

I think Tufa rock is safe but please treble check first. Not sure how well it would work for filtration. In theory I would think it would work ok as its very porous (though probably not much de-nitrification going on in there).

You would have to stock very, very slowly though and I would say you would need at least half the rock to be LR to get it too seed any time this year.

If its FO then you could just go for a couple of large canister filters (or better yet drill the tank for a sump and fill the sump with bio-balls). Then just do a fishless cycle using bottled ammonia (like you would a FW tank, details of fishless cycle is on this site somewhere). Then it doesn't matter what rock you use (within reason, some rock still shouldn't be used because it will mess up your PH amongst other things).

 

[ColdwaterJosh]

If the Tufa rock is very porous and hasn't had any copper based treatments added to it like white spot treatment for example, I should imagine it is okay to use.

If you only purchase a small amount of Live Rock it will take quite a while for the bacteria to spread across all of your rocks, but if you have time on your hands it's not so much of a problem

But if your in a hurry, I suggest you purchase a suitable amount of live rock for your tank and then let the cycle begin, but of course this is going to be ALOT more pricey

 

[fishboytoo]

If the Tufa rock is very porous and hasn't had any copper based treatments added to it like white spot treatment for example, I should imagine it is okay to use.

If you only purchase a small amount of Live Rock it will take quite a while for the bacteria to spread across all of your rocks, but if you have time on your hands it's not so much of a problem

But if your in a hurry, I suggest you purchase a suitable amount of live rock for your tank and then let the cycle begin, but of course this is going to be ALOT more pricey

Thanks for the reply. My wife will be very happy now, as I think you have indicated the fatal flaw in my plan. I have used copper in that tank before-not for ich but I read it might clear up black brush algae. This means that tufa is a good reservoir for copper. I believe that would rule out any invert CUC, but would it mean no fish??

There is no room for a sump, but I do have 2 canisiters running on it. I could fill those with bio-balls. I had been thinking carbon or phosban for the canister.

Does this mean that this TANK is forever off-limits for Cu sensitive inverts ie. corals+shrimp+snails, etc? Or would it be okay if all the contents were replaced? My 33 gal has had copper treatment and now has algae shrimp and snails in it with no problems, makes me wonder what the cutoff levels are.

 

[xxBarneyxx]

Its a tough call. The Tufa rock is definitely a no go if it has had copper treatment used with it (it will definitely have absorbed the copper and could leech it into the water for some time).

With regards to using the tank. I have used a tank for a reef set up that had previously been used for FW where copper treatments had been used (though it had been about 2 years as a FW tank without any copper used in it before i switched it to marine). I filled it with RO first and let it sit for a day then emptied it. RO water will help remove any traces of the copper from the tank but might be overkill.

You can get copper test kits as well so this would help to determine if it is safe to use or not.

 

[ColdwaterJosh]

If the Tufa rock is very porous and hasn't had any copper based treatments added to it like white spot treatment for example, I should imagine it is okay to use.

If you only purchase a small amount of Live Rock it will take quite a while for the bacteria to spread across all of your rocks, but if you have time on your hands it's not so much of a problem

But if your in a hurry, I suggest you purchase a suitable amount of live rock for your tank and then let the cycle begin, but of course this is going to be ALOT more pricey

Thanks for the reply. My wife will be very happy now, as I think you have indicated the fatal flaw in my plan. I have used copper in that tank before-not for ich but I read it might clear up black brush algae. This means that tufa is a good reservoir for copper. I believe that would rule out any invert CUC, but would it mean no fish??

There is no room for a sump, but I do have 2 canisiters running on it. I could fill those with bio-balls. I had been thinking carbon or phosban for the canister.

Does this mean that this TANK is forever off-limits for Cu sensitive inverts ie. corals+shrimp+snails, etc? Or would it be okay if all the contents were replaced? My 33 gal has had copper treatment and now has algae shrimp and snails in it with no problems, makes me wonder what the cutoff levels are.

Yes i'm afraid that does mean no inverts or corals as the copper has been leeched into the rock, but it's not all bad news. My tank which i'm running now had copper treatments added to it, I just simply washed it all out with RO water and it has been absolutely fine

Although for a 90G tank, your looking at a fair amount of live rock, but if you are patient and buy like 30kg of Live Rock and then reef bones and leave it for a while and let the bacteria spread you will be saving alot of money. I mean leaving it a good 2 months to let all the bacteria colonise. You can add some shrimp and crabs to watch, but fish will have to be after your nitrogen cycle

 

[fishboytoo]

Thanks for the replies. Let me see if I understand correctly.

Okay, so the tank is not a lost cause if I wash it out with RO water. Everything in it needs replacing however ie. tufa and sand.

Washing the tank should then make it ok for inverts and/or corals in the future. That's good news!

This would mean a sizeable purchase of live rock to make this go forward ideally, which sadly is not likely right now.

I am wondering if this can be done without substantial live rock-maybe 10-20lbs. What type of filtration is used for fish-only with no live rock set-ups? I have 2 canisters on the tank now. If I changed out the silica sand for aragonite and removed all rock would this work? What type of media would I need to run? bio-balls? chemical media?