Restoring a neglected tank back to its former glory

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Feb 12, 2016
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It's been a while.

I could write a long paragraph about my year but suffice it to say, the last year and a half has been not so great. A lot of things ended up neglected, and my fish did not escape that.

I'm trying to get my life back together and pick up neglected things where I left them off, this is number one on the list. So, to force myself to keep plodding through and actually giving my fish the care they need and deserve, I'm starting a journal.

If anybody wants to give advice as I go along on this journey of restoring the tank, please feel free to. I do NOT need to hear about how cruel it is to neglect them, as I am well aware of it and anybody pointing it out is only going to be counterproductive.

To begin, it's actually the middle of the night right now, but I'm starting this thread so I make myself actually go through with it. But, tomorrow I am planning on doing a 50% water change. I can't do more for a couple reasons; if I unplug my filter it likely won't start again and I can't afford a new one, and my bucket doesn't hold much more water than 50% of the tank.

Tank is 10 gallons, the fish currently living in it are 4 Harlequin Rasboras, 2 monkey loaches, and one cory I.. actually forgot the species of. Her companion died a couple months ago and I didn't think it would be humane for me to buy another with the tank in its current condition.

Will update once I vacuum it tomorrow.
Hi and welcome back :)

if the tank has not been water changed for a while, then top it up slowly over a couple of days. Then do 10% water changes each day for a week. Then do 20% water changes each day for a week. Then do 50% a couple of times during the week. Then do 50-75% each week.

You should gravel clean the substrate when you do the water changes.
Make sure any new water is free of chlorine/ chloramine before it is added to the tank.

The idea of slowly refilling the tank then doing small water changes is to reduce the possible shock to the fish. If the tank hasn't been maintained for a while, the pH could be very acidic and the nitrates could be very high. Suddenly changing the pH could kill the fish. So small water changes and slowly work up to bigger ones.

What sort of filter do you have?

Is the filter working properly or is it playing up?
If it's playing up then don't clean it until you can afford a new one or a new motor for this one.

If you can remove the filter materials without turning the filter off, then give them a clean in a bucket of tank water.
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What sort of filter do you have?

Is the filter working properly or is it playing up?
If it's playing up then don't clean it until you can afford a new one or a new motor for this one.

If you can remove the filter materials without turning the filter off, then give them a clean in a bucket of tank water.
Hey, I appreciate the response!

Filter is a HOB filter (Marineland Penguin 100, I believe), it was recently replaced due to storms ruining the old one. (Power flickered one too many times for the old 75...) It's currently working properly, however I don't want to turn it off and let it drain, mainly from fear it'll do the same thing as the last and take some fiddling around before it either turns on or breaks. If I do end up turning it off to do a larger water change I'm definitely going to do that on a day I have a ton of time to fix it, so likely only a weekend.

The only thing I have actually in the filter (besides the parts of the filter such as the tube) is a carbon filter pad thingy and the biowheel. I've been replacing the pads about once every three weeks as with this new filter it actually overflows if it gets too nasty.

It never actually occurred to me about shocking the fish! I refilled it about a week ago (the water was a couple inches from the top of the tank), so it doesn't need to be refilled again before I start water changes.

I'll try 10% changes this entire week.

Thanks so much for the advice! I really appreciate it.
If you have carbon in white filter material, you can cut the white part open and chuck the carbon away. Then squeeze the filter material out in a bucket of tank water.

If you want carbon then buy a box of highly activated carbon and put some in a mesh bag/ stocking, rinse and put it in the filter. But you don't normally need carbon in a filter and you only use it if you have chemicals in the water that need to be removed.

You can put a round sponge over the intake of your filter for more dirt trapping ability. And you can usually squeeze a few sponges inside the filter. Then you take the sponges out every couple of weeks and squeeze them out in a bucket of tank water and then put them back. It saves a lot of money because you aren't constantly buying filter pads to replace.
First change complete! 10-15% (I may have gotten a little carried away...) water change (I did vacuum the gravel as well, that's why I got carried away.. it's satisfying to see the filth sucked away into a bucket), I cleaned the light as it had a ton of algae on it, and I rinsed the filter pad.

I sat and observed the fish a bit and I noticed a couple things. First, the smallest monkey loach (named Annie, she's so adorable) kept trying to climb up the walls of the tank, it looks like she's gulping air when she gets to the top. I also saw she's breathing quickly and her gills are red. So I looked at the other fish and their gills are red as well, especially the other bottom feeders... It makes sense, considering how filthy the tank got, that they'd have ammonia poisoning. Considering that, is there anything else I should do other than the water changes? Or will the water changes be enough?
I assume you dechlorinated the new water before it was added to the tank?

That is unlikely to be ammonia poisoning and more likely to be sulpha dioxide poisoning. When you gravel cleaned the substrate, did any of the sediment end up floating around the tank? If yes, there is a chance that some of the gunk was holding anaerobic (lacking oxygen) bacteria and may have had sulpha dioxide gas in it. A tiny amount of this can kill fish quickly.

The best thing to do is increase aeration immediately and keep it high for a couple of days.

When you gravel clean substrate that hasn't been done for a while, you should push the gravel cleaner into the substrate and lift it up a tiny little bit. Then hold the gravel clean there until no more gunk is being sucked out of the gravel. Then lift the gravel cleaner and push it into another area and do the same thing.

If you have anything to reduce stress in fish you could add some of that.
Ooh, yikes, I'll see what I can do about aeration. I have a pump that's intended for 30+ gallon tanks that puts out WAY too much air (that I used when the filter died)... Will this be good or just stress the fish too much?

And yes, I did dechlorinate the water before adding it.
I put the air stone in, and now they're acting a little more normal. Though they do seem intrigued by the air stone.

I'm gonna try to get another water change in tomorrow, maybe I'll be able to vacuum quite a bit of the substrate.
Second water change completed! I was able to vacuum a bit deeper into the gravel this time. The cory is sitting right over where I just vacuumed, she doesn't usually sit there.. maybe it's a bit fresher right there?
it might be cleaner where the cory is sitting now, or it might just be more interesting since it's been turned over :)
Third water change is complete. The spots I vacuumed yesterday already have a ton of filth in them, though not as much as before.

I tried vacuuming the roots of the plants, but the stuff I thought was just general poop and stuff wouldn't vacuum off. I suspect it would come off if I rinsed them by hand, but I'm not sure if it'll hurt the fish or not. I'll take pics and upload them later.

The first time I do a large water change (where I turn off the filter and everything) I'm going to take out the cave. I'm not entirely certain I've ever vacuumed under it since I can't without removing it, and the plants are connected to it.

In 2 weeks I'm going to "rip the Band-Aid off" and turn off the filter, clean the intake, take out the cave and vacuum under it, probably pull out the plants to clean their roots (presumably figure out how to bury the plants a little better as well), and that'll probably have to be a 75% water change day, because it's a pain to turn the filter off.

The fish are a lot more active since I stopped neglecting them and started this process. The cory's gills are a lot less red/irritated, as well. The harlequins are showing vibrant colors. I think they're all happier.

The only issue is the snails. There are SO MANY humongous snails that are beginning to die since they've been there for years. Kyle, my snail-eating monkey loach, has gotten so large I'm somewhat concerned he's gonna have some serious intestinal issues, if not death from eating way too many snails. Yet they're still dying off pretty fast, almost every time I walk by the tank I see another dead snail that hasn't been eaten yet. With each water change I've plucked a few out, usually 3-10 snails per water change. I think the dying snails (and pooping snails too) are adding issues to the already poor water quality, I just don't know how to get rid of them.
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Don't pull the plants out or gravel clean where they are. Just leave the plants alone and gravel clean around them.

If you have plants that you want to move you can carefully lift them up while holding the gravel clean near them to suck up the gunk, but as a general rule you don't gravel clean where the plant's roots are. Gravel clean around plants but don't pull them up to gravel clean under them.

If you have a cave, remove it and gravel clean under it but keep the filter going. Just go through the tank and gravel clean it all before turning the filter off. If you gravel clean under the cave and turn the filter off at the same time, and the filter does not come back on, there could be issues. I would do the filter separately and after gravel cleaning and water changing the tank. Basically do a gravel clean and water change, wait 24 hours, then do the filter. After the filter is clean and working again, wait 24 hours and do more gravel cleaning and water changes.

Some snails are easy enough to remove by hand or a small fish net. Others need to be lured out with some fish food. However, because the tank has been neglected a bit, I would not suggest baiting because it could cause water quality issues. I would just scoop out any you find when you see them and leave it at that. In a month or so when the tank is back to normal, you can try making a snail trap.
Ahh, I never thought about the filter (though in the back of my brain I did think about it... subconsciously), that's definitely a better option than what I was gonna do.

I'll keep doing what I'm doing with the snails (picking them out by hand). I'll look into snail traps for when I get the tank back under control, though.

I really appreciate all the advice, by the way!
I cleaned it again on Saturday (I missed Friday due to an unforseen personal issue, which did get resolved but made it impossible to vacuum on Friday), I'm about to go vacuum it again today.

The fish look happier, certainly, and the gravel looks a lot cleaner. The water is gradually getting clearer.
Cleaned today! I went ahead and replaced the carbon filter, since I haven't been able to get the round sponge yet, and the filter wasn't letting anything through it. So it SHOULD be another month or two before I gotta replace it again.. hopefully. I'm getting to the point that I can't afford the new filters (since I'm 14 and have no income), so it'd be good to get the sponge soon.

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