Dying Plecos

[DWhitehead]

I started keeping fish two and a half months ago. I got a great deal of help from the guy at the local store, and my aquarium has now cycled. I've lost a few fish over the past month, but generally these were fish that had experienced the cycling process and might have been weakened by, for example, the initial nitrite spike.

A week and a half ago, I bought a small bristlenose pleco. He looked fine for a couple of days, then starting slowing down and died about five days after I bought him. I did some reading about his species, so on Saturday I decided to try again. This time I had driftwood in the tank and spirulina tablets to put in at night. The second one died last night, so it lasted about two days. Not good.

I'm going to try again, but I'd like to sort out what's happening first. My other fish are not having such problems. The notable difference is that plecos suck everything in the aquarium, so perhaps there's some residue making him sick?

Some details: 70 liter tank, no ammonia or nitrites, nitrate at 20-40 ppm, ph about 8.2 (high I know, but that's the local water -- the fish store uses that ph and acclimates its fish to it, so I do the same.) Fish: we have eight neon tetras, two guppies, two mollies, two x-ray tetras, two corys, a dwarf neon gourami and a betta. A bit of a potpourri, but this is my children's tank -- I just have to do the work.

Also of note: one gourami, which died a while ago, looked like it had finrot. A number of the other early fish also have fins that don't look great. The local store gave us a red liquid (I don't have the name handy) which you are supposed to put into your tank for three days (25 drops/12 drops/12 drops) and which is supposed to cure a number of bacterial problems. I gave them this treatment three times; two of the treatments were several weeks ago, but I did one more just after buying the first pleco. There's seems to be a bit of red residue on some of the structures and fake plants in the aquarium, and I wondered if this could have come from the disease treatment. Could it have hurt the pleco?

Another odd note: the other four fish that have died were all females (the aforementioned gourami, a guppy/molly/platy.) Coincidence I'm sure.

Last comment: I added a liquid that is supposed to reduce nitrates on Saturday. It is supposed to be harmless to fish.

 

[Maxta]

Sorry to hear that buddy. I lost my pleco a few weeks ago and he was my pride and joy even though i hadnt had him long. Maybe the tank isnt established enough to have a Pleco already (someone told that to me).

How often do you do water changes, and how much? Are you treating your water with conditioner before adding it to the tank when doing water changes. Whats the temperature of your water? What are you feeding the Pleco?

I dont have the answer for you but some of the above information may be helpful for others to help you identify what the problem was/is.

 

[connorsbala]

I have the same sorta size tank. My pH is a lil lower than yours. I havent had good expwerience with tplecs, L134 dying an dclown plecos dying(money going down the drain )I htough tmy pH was 7.5 which is well to high for plecs. They like it between 6-7.5 so id say its from that as thats what mine died of!

 

[dwarfgourami]

I htough tmy pH was 7.5 which is well to high for plecs. They like it between 6-7.5 so id say its from that as thats what mine died of!

That wouldn't apply to a bristlenose though. My ph is good deal higher than yours and my bristlies are breeding like they thought God's commandment to fill the earth was addressed to them.

My guess would be that your bristlie was a little too young to cope with the shock of moving. They can be quite sensitive when they're tiny and need careful acclimatising. Better to buy bigger if you can.

 

[DWhitehead]

I change about 10L of the 70L weekly. Lately I've added "Cycle" and "Waste Control" to the water change, although I've read at least one site that says that adding extra beneficial bacteria might increase the nitrate level. So I'm not sure if that's the best idea.

The water temperature is 25.

I mostly feed flake to the fishes, and most of the fishes are schooling fish and feed on the surface. So that's why I thought the first pleco might be starving. But I had both algae tablets and some pellets for the second pleco, and he was gone in two days. Perhaps I just got a bad fish -- the first one looked ok for a couple of days, while the second never really looked happy.

The only reason that I doubt the pH explanation is that that is the same pH as the plecos are being held in in the local shop, and their plecos aren't dying.

 

[connorsbala]

Oh fair enough! but the ones on then newt and around where i live are kept in RO water which has a neutral pH. I was just sharin gmy story,sorry it didnt help!

 

[Tessla]

A few things to note about your current stocking: mollies will do better in brackish water, otherwise they need extremely clean fresh water which will be next to impossible to acheive with a pleco in your tank. If you have a male betta, he shouldn't be kept with tetras, gouramis or male fancy guppies. Tetras will nip at the long fins, gouramis and male fancy guppies are seen as competition and will likely cause some fights to break out. Corys prefer to be kept in groups of at least three of the same species, though at least five would be better.

Considering everything you've got in there right now, your tank is pretty well stocked if not a bit overstocked at the moment, definitely not enough room for something as messy as a pleco in there. If you sort out your stocking a bit, you might get away with a pleco in a few months once your tank is more mature. However, if you're planning on keeping the corys in there, I'd swap out a couple of the less suitable fish (say the mollies and the betta) for a couple more corys of the same species.

Plecos don't really like new or unstable tanks, they'll do best if you can put one in a nice mature tank. You've also mentioned that you've been adding medication to the tank: you never ever want to add new fish to a tank being medicated. Medication can (and should) be removed by the addition of activated carbon in your filter (don't really need it otherwise, and definitely don't keep it in your filter while medicating) and doing water changes once you've finished treating. Before you add anything else to your tank, sort out any disease and water quality problems first or you'll risk passing it right along to your newly added (and already stressed) fish. The only chemical you should be adding to your tank once you've got everything sorted out should be dechlorinator. Nitrates should be taken care of in weekly water changes (20-40ppm is fairly low), ammonia and nitrites should be zero at all times if your filter is mature. pH is also fine, I've got awful tap water myself and it hasn't killed a fish yet.

Other than the things I've mentioned, your maintainence sounds good, I'd keep that up until you've got a more mature tank.

 

[DWhitehead]

That's all very interesting. You're saying that plecos make the water significantly dirtier? I didn't know that; I just thought they'd help eat any algae, which I thought would make the tank cleaner. Of course, feeding them with algae tablets definitely makes things dirtier. I'm happy to do without a pleco for a while if it's not suitable for the tank yet. I just thought an algae-eater would be nice.

 

[summ3r_daze]

You're saying that plecos make the water significantly dirtier?

Think poops.

 

[Tessla]

Plecos are little (well, some of them are really big) poop factories, if the only reason you want to keep one is to clean up algae, get an aquarium safe scrubbing sponge instead and save yourself the water changes. The presence of algae isn't actually a bad thing, it actually helps clean up your water by using up excess nutrients (including ammonia, nitrites and nitrates) so I usually leave it on every surface but the front glass. A better way to get rid of it would be to decrease your hours of lighting and understock your tank so that there isn't as much algae food being produced by your fish.

I happen to like plecos and various other bottom feeders so much that I tend to stock my tanks around things like loaches and catfish. The only thing you'll have to remember when keeping a pleco or other "cleanup" fish is that they're often very high waste producers themselves and you'll want to make sure that you have the space in your tank. The only cleanup species I can think of that don't produce massive amounts of poop are the algae shrimp. Amanos and cherry shrimp are the easiest to come by, they stay small and practically don't count towards stocking.