Re-Cycling 20G tank, hasn't seen fish in years; also need advice, 125g with two fish
This thread's a bit of a two parter, so bear with me a bit.
First off, my parents decided to completely clean out their 125 gallon tank, as the last fish in there, a dinnerplate-sized kissing gourami, had died after being mostly alone for at least six or seven years. They proceeded to completely replace the Biowheel filters and did not attempt to re-seed them in any way or change the wheels one at a time (fearing diseases from the previous tank tenant), and then performed a 75% water change and siphoned the gravel and reserved a good bit of the gunk on the bottom, hoping that would house enough bacteria to keep the tank cycled. They went out yesterday and bought eight fish, six of which (two phoenix tetras, two tiny clown loaches, and two tiny catfish that I'm not sure of the species) died within hours or overnight despite an emergency additional 1/3rd water change. I am worried for the two blue gouramis that remain, although thus far their behavior is fairly normal (swimming about calmly, eating well, etc.), while the other fish were acting sick within an hour of being placed in the tank despite my parents floating the bags for 30 minutes prior to introducing them. Here are the chemical parameters of the 125 gallon tank:
Secondly, I'm currently looking to prep and cycle our empty 20 gallon tank to receive the blue gouramis as soon as possible, but it's had water filtering through it for a few years and nothing visibly living there but a bunch of algae. I ran out and got a new test kit and a gallon of surfactant-free ammonia to get the cycle started, but I'm not sure if I should do anything special because the tank has a nonzero level of nitrate and there is a thick and healthy bed of algae covering every surface. Here are the chemical parameters for the 20 gallon tank:
Note that this tank also has a HoB TopFin 20 filter paired with an undergravel filter with powerhead. There also appears to be an in-tank heater inside, but I'm not sure if it still works.
Should I scrub off the algae, empty the tank and try to start from scratch, or is there any value to keeping the water the tank has right now? Should I also get new gravel for it? I also don't have much to seed the tank with, other than rocks from my new axolotl's tank (his previous owners had him on river rock and I am getting rid of it to put sand in - is this a suitable seed? His water is free of ammonia and nitrite and only has about 2.5ppm nitrate) or gravel from my cycled 2 gallon betta tank.
I apologize for the length of this thread, but as you can see I have quite a mess on my hands!
Hi and welcome to the forum
Regarding the 125 - Since all the filter media was replaced, and since the largest % of beneficial bacteria live in the filter and media, the cycle in that tank was lost. There may have been some bacteria still alive in the substrate unless was without fish for several days and if so, it would have died too.
My guess would be that the fish died from shock. the PH is low and may differ greatly from the fish store water where you bought them. It might have been preferable to drip acclimate them to reduce the shock. The ammonia is higher than preferred, even in an uncycled tank and the nitrates are high but that shouldn't have killed them. Also, that's a pretty low temp for tropicals. most keep theirs around 78. I'd suggest returning the surviving fish, changing out all the water, cleaning the substrate and completing a fishless cycle on this tank. I shouldn't take more than 3 - 4 weeks and then you can stock it however you want.
Regarding the 20 - even if the tank has been running for months, if there are no fish in it, there is nothing to feed the BB in the filters. so the cycle on this tank is lost as well. I would also do a fishless cycle on this tank. See the fishless cycle stickie in the beginners section and then let us know if you have problems.
As for the algae - if it were my tank, I'd want it out of there so I'd start from scratch on this one too. And the temp again, should probably be around 78. Note too, most here are not fans of UGF's. You might to get that out of there as they have proven to be nitrate traps.
Good luck and let us know if there's more we can help you with.
Thank you kindly for the reply! I had already checked out that thread, but wasn't sure if there was anything specific I should do for this situation. I will talk to my parents about returning the gouramis, but I don't know if they'll be too thrilled to seek that option. In the meantime, I'll empty out the 20g and start over.
What about using my axolotl's rocks as seeds for bacteria? How about betta gravel? Should I use a bit of both and see what happens?
Maybe someone else can address the axoltol rocks. I've never heard of them or betta gravel. to my knowledge there only 3 ways to cycle a tank
1) with fish which will take 2 - 4 months and tons of water changes
2) without fish seeding the tank with pure ammonia and 0 water changes until just before you stock
3) using established filter media from a fully cycled tank which would give you an instant cycle and you could stock immediately.
Again, very little BB lives in the rocks or substrate. The bulk is in the filter media.
The betta gravel is the substrate in my betta's tank, the axolotl rocks are the substrate in my axolotl's tank, sorry for the confusion. I was asking if there would be any notable increase in the cycle's pace by adding etiher. And I know that the bulk of it lives in the filter media, but my current filters in both the betta and axo tanks are both cartridge-based so this makes it quite difficult - I'm scrambling for any possible solutions to save the gouramis because I am fairly certain my parents will not listen to reason and return them.
I'm sorry you have to restart your 20g tank. As a beginner myself, may I offer a different approach?
Instead of starting over with new everything (which is quite costly, I imagine) with the presumption that the nitrifying bacterial population is absent, why not do a simple test? Change the water so that the nitrate is down to a negligible ppm, and then proceed with adding ammonia to the water as if you were doing a fishless cycle on a 20g tank. If your ammonia is converted to nitrates, then you must refute the original hypothesis that nitrification is absent. If your ammonia remains, then you will have to re-invest in cycling, by whichever method that works best for you.
From reading a lot of these posts, it becomes readily apparent that, while well-meaning, many members are quick to insist on one method over another, or prescribe strict regimes that are based on anecdotal evidence and personal experience. While very valuable to appreciate others' experience, you are ultimately responsible for judging recommendations and enacting a course of action. Good luck with your tank!
May I chime in here plz?
First your gourami most likely didnt die of anyhting tragic BUT if it did, it would be wise to take the tank down completely. This involved washing the gravel (all that is there is half decomposed poop...) and you can wash it in a mild bleach solution or just a lot of water. Take a mild bleach solution (3 parts water to 1 part bleach) and scrub the entire tank, walls and all. The entire point of this is to get the tank back to ground 0. You have already cleaned the filters where the heart of your aquarium lies so a fishless cycle should be done.
I dont think it was PH shock that killed the fish, I didnt see a mention of dechlorinator or some product like Prime mentioned. It will lightly detox the water put into the tank. I also think we should sit down and work out a stock list while a fishless cycle takes place in this tank. Take the fish back and lets talk this one out. The gouramis will survive because they breathe air when water conditions are poor... just not well...
Now In regards to the smaller tank... Complete a fishless cycle. No hypothesis neccisary. If you can get to the point where 2ppm of ammonia is eaten daily then you are ready for fish. Theres thread upon thread on the forum about this. No addition of substrate is neccisary. Remember that axxo's are much different than general fish and not every fish is equal. Discus are much more susseptable to things Malawi cichlids are just fine with... parasites, bugs, other little nasties... its all in a tank and the best solution for everything is to just flat out start over with a clean slate and set it up right from the bottom.
FW: 1 45gal, 1 40gal, 3 10gal, 3 30gal all community tanks of different species
Sw: 1 55gal, 1 30gal show, 1 29gal show, 1 20gal and 2 10's
Yeah, the 20g has been empty for several years, there's no way any of the nitrifying bacteria I want are going to still be alive. I'm not sure why my parents didn't straight up drain the thing if they weren't going to have fish for that long. I just wasn't sure if I was going to be tossing out anything else potentially useful, such as any beneficial microorganisms that don't perform nitrification, by draining it and starting over. Since that is not the case, I will start from the ground up. Should be fairly straightforward, but I know where to go if anything stumps me.
If I take a small bit of spare filter media that wasn't actually put into the 125 gallon and stuff it into my betta's filter along with the existing media, will that allow me to produce a bacteria seed for either one of my tanks? How long should I leave it in there to achieve that effect? I'm considering doing this anyway to baffle the filter, as the current is too strong for him to make a lasting bubble nest, but if I can use it to help my parents' fish fiasco so much the better.
I did indeed use an appropriate commercial dechlorinator; my betta and axolotl would both be very unhappy customers if that wasn't my standard practice when caring for aquatic animals. Please do note that I have a good deal of aquarium experience, I just haven't done a fishless cycle before, especially not in an odd situation like this.
A stock list will not be necessary, as I will not be the one stocking these tanks at the end of the day. I'm only here because my parents thought that asking the biology/chemistry graduate to step in and correct the water chemistry problem would be the right thing to do; I'm happy to address the problem for them, but I want the advice of more experienced aquarium keepers on my side while I do so. Thank you for the offer, however.
As for the old kissing gourami, he was getting to be about fourteen or fifteen; Mr. Tickles was blind and we all feel that it was his time to go. No tragedy there, just the circle of life.
Thanks again, folks!
In addition, extra thanks to you, myofibroblast; asking these sorts of questions can be rather daunting, and I'm glad that I'm not alone in feeling that way.
Last edited by exrocketsled; 03-05-2013 at 06:07 PM.
No worries, was just throwing out some thoughts. Good luck with both your aquaria!
Originally Posted by exrocketsled
I merely wondered if we might be presuming too much with regard to the presence or absence of nitrifying bacteria in your tank, even if they have been without ammonia as a source of energy for a long time. The rationale for pointing this out is that nitrifying bacteria, in my brief 10 minute review of literature, are quite hardy creatures. I never underestimate the resilience of environmental bacteria, especially ones that live in low-nutrient conditions for billions of years (or 6,000-7,000, if that's your faith/believe). Nitrosomonas and Nitrospira spp seem to be one of these, constantly having to compete with heterotrophic bacteria in the low-ammonia natural environment for substrate (food).
If you do a quick search on Medline/PubMed or Google, you'll find many interest in nitrosomonas spp, dormancy, reactivation after dormancy, as well as effects of biofilms (think a group of bacteria that created a little slime house/community) on starvation and reactivation. I have read some people have had experience with cycling at a much faster rate using a few year old gravel that had been left dried, stored in storage for a few years, before being used in a new tank again. Anecdotal, of course, but nonetheless intriguing.
I'm definitely not shy about asking questions (isn't that why we're here?), so there shouldn't be any feeling of being daunted by people who have done this for many years. What is the worst they can say, that we are beginners? That we lack knowledge? It may very well be true, and that is why it's called the beginners' circle! :-)