Adopted a 55g - Maybe Oops?

[Bent Needle]

So, I'll try to make this as short as possible, but that's hard for me.

TL;DR - I adopted my friend's husband's 55 gallon tank that he no longer wanted in their (admittedly tiny) house, and now I think there may be big problems with the stocking.

From what my friend said it sounded very well managed and happy and like there would only be the usual challenges of acclimating fish to new water and of course the stress of transport. It looked lovely and had been setup with these five fish in it for about two and a half years. 5 medium size fish in a 55 gallon sounded decent to me, especially with a canister filter and considering they've been happy and healthy for that long. Today they delivered the whole setup to my house. The tank is clean except for some algae (nothing over the top, and to me means a decent bacterial colony), the fish seem pretty calm and chill after having a couple of hours in a dim room. However...I just put them all and the equipment into AqAdvisor (what I've used to make stocking and equipment decisions in the past), and I'm worried. It says that the tank is overstocked (107%), and needs more filtration (at 77%). Fish are as follows:

2 adult angelfish
1 Redhead Severum, ~5-6" long
1 Chinese algae eater, ~4-5" long
1 common pleco, ~12" long


AQAdvisor also warns that the severum and algae eater are not done growing at these sizes and will cause significant problems as they get bigger (the Severum for filtration, the algae eater because of aggression). I was a little shocked at the size of the common pleco - which I knew could get huge but I'd never seen one this big except in a store - it managed to get the entire room wet when we tried to get it out of the bucket without touching the spiny back!

Please give me opinions. Is AQAdvisor just super conservative and these fish will be fine, since they've already been fine so long? Or do I need to plan to downsize the residents/increase filtration/something else?

Pics attached with the fish on the (saltwater) background crossed out.

 

[Andy Sager]

Yes, AQAdvisor is a little over the top conservative. That said, the pleco is really too big a specie for a 55 gallon tank and if you can, I'd exchange it for smaller varieties that won't get that large.
The Severum by itself should not be too much of an issue if you keep the stock number low. If you want to add more fish, you may want to consider trading in the Severum as well. Since the one you have is a man made variety, it's hard to tell just how large it really will get. This is a pic of a Severum at my Buddy's store. It was a wild caught fish. Just so you know, the divider it is facing is at 36" from the end of the tank. https://www.aquariumadvice.com/forums/members/41382-albums14916-picture73244.html

As for the algae eater, if it's getting enough food, it shouldn't be too much of a problem. That said, there are mixed opinions on whether they are good fish for community tanks. They tend to be more of a loner fish and may get aggressive towards other species their same size. So if you keep the fish well fed and don't try to add other fish it's same size, I wouldn't be too concerned.

 

[Bent Needle]

Holy...that thing is HUGE!!!

Ok. I was also leaning towards taking the pleco in to my local store, maybe get a smaller variety or a couple of bristlenose (what I've had in my smaller tanks before). The algae eater is super pretty and not very big right now so I'd like to keep it unless size or aggression becomes an issue. But we'll see, fingers crossed.

 

[Andy Sager]

Holy...that thing is HUGE!!!

Ok. I was also leaning towards taking the pleco in to my local store, maybe get a smaller variety or a couple of bristlenose (what I've had in my smaller tanks before). The algae eater is super pretty and not very big right now so I'd like to keep it unless size or aggression becomes an issue. But we'll see, fingers crossed.

Yeah, it is. People forget that those cute little fishies we get when they are so cute and small ( look at Pacus :^0 ) can turn into MONSTERS!!!! ( Pacu can get over 75 lbs ). But again, this was a wild Severum and you have a genetically modified Severum so it probably won't get that large.... but who knows.

As for the Algae eater, I'd wait and see IF it becomes a problem. Just know that if it gets aggressive or causes problems, "he gots to go." He won't change back into a nice fish.

 

[Bent Needle]

Thank you for the advice/opinions! This is more or less what I was thinking, though I didn't know the algae eater could be so problematic. Guess I'm taking a trip to the store today to beg them to take a med-large pleco off my hands...haha!

 

[Andy Sager]

Thank you for the advice/opinions! This is more or less what I was thinking, though I didn't know the algae eater could be so problematic. Guess I'm taking a trip to the store today to beg them to take a med-large pleco off my hands...haha!

Good luck.

 

[Bent Needle]

Record scratch, new problem update:

I went to the fish store to see about surrendering the pleco, they said no problem they would be happy to take it. Whoohoo, problem solved (once I an get him out again, anyway). I also picked up a nitrate test kit since that was the only thing the original owners didn't have in their test kit. Ammonia was at 0 ppm after a ~60% water change for the transfer yesterday.

I just tested the nitrates and it read 160+ ppm. This isn't my first time using a kit, I followed the instructions EXACTLY and when I got that I immediately repeated it because I thought surely not...but no, it is the deepest darkest red I have EVER seen on a test (see pic).

So my plan is to do a 50% water change and hope that reduces it at least a little. I've never had to do this, will a sudden reduction shock the fish in any way? Like if I do the 50% and that only brings it down to 80 ppm, if I continue to change until it's at 40? That's a huge water change for them from 48 hours ago. The goal is obviously less than 40 ppm but I would be happy to be at 40 for now.

 

[Aiken Drum]

Depends on how high the nitrate is. All you know is that it's above 160ppm. If its up at 400ppm, a 50% water change would bring it down by 200ppm, thats been known to kill fish.

You might also find severely depleted carbonate hardness, and a big water change will suddenly increase it. A big shift in disolved minerals isnt good either.

You could half fill the test tube with tank water and half fill with tap water and test that. Double the result. That might give you a better indication where you are. Assuming your tapwater is zero, or at least very low.

Personally i would do 25% water changes, an hour or so apart rather than 50% + water changes so you dont cause such a big shift.

 

[Bent Needle]

Hmm. The substrate is some kind of reddish rock that was definitely...degrading, I guess? when it was moved yesterday all the water was tinted that color. I wondered if that could be part of the high reading but it has been 24 hours since the water change.

Tested my tap water just in case but it reads 0.

I just don't want to hurt or stress the fish more than they already have been. Guess I'll start with a 25% and go from there.

 

[Aiken Drum]

Well nitrate comes from ammonia, so if your disturbing the substrate disturbed a lot of organic waste, this will have decomposed to ammonia and then your nitrogen cycle will consume the ammonia and turn that into nitrate.

So that could explain high nitrate levels if they arent normally high. It would take a hell of a lot of ammonia to produce 160ppm + of nitrate though. Enough to kill fish on the spot.

How did you move the tank? Did you reuse the original water from the aquarium? Or is it all new water so in effect a 100% water change? How long ago did you move the aquarium?

 

[Bent Needle]

They used about 25 gallons of the original tank water, hence my guessing at about a 60% water change. It was moved yesterday morning so about...30 hours ago.

 

[Andy Sager]

I would do 25%-30% water changes 2 times per day about 12 hours apart. I'd do this daily until you get the nitrates down to below 40. This will reduce the stress of a drastic/ large volume water change.
Sadly, large Plecos produce a a lot of waste so this can account for the higher nitrates. All that Poo in the substrate may not be getting fully filtered out so it was sitting in the substrate. Once disturbed, your biological filter starts breaking it down more seriously so you get more nitrates eventually. You shouldn't have the same issue once you get the large pleco out of there but you do need to keep up with water changes weekly between the Adult Angels and the larger Severum. They may not be the poop machines that the pleco is but they are still large fish and large fish sh*t large sh*ts.

There is another option to the multiple water changes only which is a nitrate removing pad or pouch in the filter. API makes this: https://www.amazon.com/API-NITRA-ZO...lpcontext&ref_=fplfs&psc=1&smid=ATVPDKIKX0DER , Seachem makes this: https://www.seachem.com/purigen.php and there are others. In both cases, I would still be doing water changes to assist these to getting below 40 PPM nitrate but they will help in keeping the new waste from being converted into nitrates while the water changes are doing their thing.

 

[Aiken Drum]

Id say the high nitrate is a long standing thing, if its 160ppm + now after effectively a 60% water change, then it will have significantly higher before that before the move. If the high nitrate came because the substrate was disturbed during the move you would be talking about 50ppm of ammonia being released which the fish wouldnt have survived.

Any idea what the water change schedule was before you took the fish? I would want to see 50% weekly with those fish in that tank to keep on top of nitrate levels. Interesting that it didnt seem to effect the fishes health.

 

[Bent Needle]

I would do 25%-30% water changes 2 times per day about 12 hours apart. I'd do this daily until you get the nitrates down to below 40. This will reduce the stress of a drastic/ large volume water change.
Sadly, large Plecos produce a a lot of waste so this can account for the higher nitrates. All that Poo in the substrate may not be getting fully filtered out so it was sitting in the substrate. Once disturbed, your biological filter starts breaking it down more seriously so you get more nitrates eventually. You shouldn't have the same issue once you get the large pleco out of there but you do need to keep up with water changes weekly between the Adult Angels and the larger Severum. They may not be the poop machines that the pleco is but they are still large fish and large fish sh*t large sh*ts.

There is another option to the multiple water changes only which is a nitrate removing pad or pouch in the filter. API makes this: https://www.amazon.com/API-NITRA-ZO...lpcontext&ref_=fplfs&psc=1&smid=ATVPDKIKX0DER , Seachem makes this: https://www.seachem.com/purigen.php and there are others. In both cases, I would still be doing water changes to assist these to getting below 40 PPM nitrate but they will help in keeping the new waste from being converted into nitrates while the water changes are doing their thing.

Hmm. Good to know about the nitrate pads and things but I think I would rather just do the water changes. This thing already has a much more complicated filter than I've ever had (a canister, Fluval 304) and I feel like I really don't need more stuff! Lol.

I did a 25% water change a couple of hours ago, just checked the nitrates again and it seems to be between the 80 and 160 range, still pretty dark but not blood red like the first one. Whew. So I'll do another one first thing in the morning and continue until it comes down to a safe level.

The fish had been reasonably active for newly moved fish, I think, even before this WC. They were all sticking to the bottom third, but I noticed after the 25% WC the angels were up in the middle third a little too. Not sure if that was just coincidence or not.

 

[Bent Needle]

Id say the high nitrate is a long standing thing, if its 160ppm + now after effectively a 60% water change, then it will have significantly higher before that before the move. If the high nitrate came because the substrate was disturbed during the move you would be talking about 50ppm of ammonia being released which the fish wouldnt have survived.

Any idea what the water change schedule was before you took the fish? I would want to see 50% weekly with those fish in that tank to keep on top of nitrate levels. Interesting that it didnt seem to effect the fishes health.

I am also completely shocked that all these seem to be healthy fish with the levels that high...I have only ever had small (20 g) tanks but I've never let the nitrates get above 20-30 ppm. I had assumed there would be some very detrimental effects with it so high, but I guess if they are reasonably hardy fish and it is a gradual thing that they get used to...

I did ask them about the waterchanges. He said his "goal" was a 50% every two weeks, but admitted he thought it had been 6 months since he did it.

Mr. Pleco will be headed to the fish store this week. They were actually quite happy to hear I wanted to surrender him as the biggest they have currently are about 4-5" long, and they have a 150/180g tank for them that only has a few swordtails in it. I'm sure it will be much happier there until it finds another real home. Hopefully.

 

[Andy Sager]

The fish are responding to the better water after the change. It's the same as why fish go to the surface when the water is low in oxygen. It's because the oxygen is closer to the surface.
There's a misconception that nitrates are harmless. Nitrates are not as bad when kept at lower levels but when they get up high, they do effect the fish as it gets into the fish's bloodstream and damages the organs so you really do not want high nitrates for long periods of time. Organs can regenerate or pass through impurities if it gets good clean water passing through them but it's not like you need to reduce the nitrate level in say 24 hours or else the fish are doomed. Lowering through water changes is always a great option but you have to keep in mind that water consists of more than just Hydrogen and Oxygen so changing too much water too quickly can have adverse affects on the fish as well. When it comes to how much changes after each water change, realistically, the percentage of water you change is the percentage of change in the nitrate level. That's immediate ( once the new water circulates throughout the tank.) You have to keep in mind tho that while you are waiting for that 12 hours to do the next water change, more nitrate is being produced by your biological filter so the level of reduction does not stay at that level for long. That goes with the amount of ammonia being produced by the fish. The more they produce, the higher the level will be at the 12 hour mark for the next water change. So you can save some nitrate reagent by only testing it once before you do the water change or, since you know it's high as it was, you can get away with testing it once every couple of days until you see it drop below 40 PPM And once it is below that 40 PPM, test daily to see how fast it reaches or exceeds 40 ppm so you know how often the water needs to be changed. Let's face it, 6 months with no water change and with a sh*t factory in a fish in the tank, it's no wonder the nitrates are as high as they were.

 

[Bent Needle]

Makes sense, I highly doubt it will be appreciably higher 12 hours after a WC.

Thank you both for all your tips and advice! Here's hoping I can make this a happy, healthy and thriving tank! I'm sure I'll be back with either more questions and issues or updates. Hehe.

 

[Andy Sager]

Makes sense, I highly doubt it will be appreciably higher 12 hours after a WC.

Thank you both for all your tips and advice! Here's hoping I can make this a happy, healthy and thriving tank! I'm sure I'll be back with either more questions and issues or updates. Hehe.

Only a test result will prove you right or wrong about that.

 

[Bent Needle]

Thanks. Thanks for that. Now I'm still going to need to test before every WC just to satisfy my own curiosity. Rude.

Amazed at the uptick in activity after the waterchange this morning. Got a definite 80 ppm reading, phew. The severum and angelfish are all swimming back and forth, exploring the water column, seem to be watching me and my dogs. The algae eater is also out and seems to be a total spaz. Can't wait to see how they do once everything is at good levels.

Short video here.

ETA: Not sure whose idea it was to put a saltwater background on a freshwater tank, but that'll be going soon. Hah.

 

[Andy Sager]

Bent Needle]Thanks. Thanks for that. Now I'm still going to need to test before every WC just to satisfy my own curiosity. Rude. Or you can test after doing the water change and do the math to figure out how high it was BEFORE you changed the water. LOL

Amazed at the uptick in activity after the waterchange this morning. Got a definite 80 ppm reading, phew. The severum and angelfish are all swimming back and forth, exploring the water column, seem to be watching me and my dogs. The algae eater is also out and seems to be a total spaz. Can't wait to see how they do once everything is at good levels.
It shows how the high nitrates were effecting the fish from the inside ( on a cellular level.) As good water flushes through the cells and they recover, the fish act better, more fish like.

Short video here.

ETA: Not sure whose idea it was to put a saltwater background on a freshwater tank, but that'll be going soon. Hah.

Maybe the original owner wanted a saltwater tank but couldn't afford one.