Problems in my established tropical aquarium

Lcc86

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Hi all

New to this forum, have been a beginner enthusiast for several years, started with 3 African dwarf frogs, the oldest of whom lived for about 7 years. When I only had one ADF left I bought 3 cory catfish who are still going about 2 years later. I also buy nerite snails from time to time.

Last year I had a problem with blue-green algae which I got under control. In about January I got 3 new ADFs after I lost my 7 year old one, they have never seemed to be completely comfortable. They spend all their time hiding and haven't grown much. I have also had problems keeping any plant alive. I have always bought elodea densa and never had an issue with it - in fact I've usually had to trim it and throw some away as it's thrived a bit too much! But since I got the baby ADFs I can't keep any plant alive for more than a week. They just turn brown and die. My filter was also getting really clogged with brown muck. The snails have all gradually died as well.

I bought a new filter about a month ago which seemed to help things, but in the last week I found one of my ADFs dead and half-eaten, and all my plants have died again. Just now I went to clear out all the dead plant material and clean the filter, and I can only find one ADF, there's no sign of the second one anywhere so am assuming it also has died and been eaten. The corys seem absolutely fine, no sign of illness or anything, but the ADF gets very stressed when I clean anything in the tank. They have plenty of hiding places but obviously plant cover is currently an issue. I keep buying new plants to replace the dead ones but they then die in turn.

Since having the above problems I've regularly tested my water with an API test kits and found no problems with my parameters (am on the train right now so can't check and post current parameters). I would usually do a water change once a week but increased that to twice or three times when I started having issues. I kept the lights off completely to tackle the blue-green algae, and have also tried to generally have the lights on less in case that's causing my plants to die (I aim for 9/10 hours of light a day).

I've been using plant fertiliser as wasn't sure if my plants weren't getting enough nutrients but it's made no difference. I'm worried that there's something fundamentally wrong with my setup that I can't seem to fix. My corys seem to be coping but am worried I'll lose my last remaining ADF soon and then maybe even my corys if I can't figure out what the problem is.

The tank is 15 litre capacity, although I would say its probably filled to about 12 litres at the moment to allow the ADF to come up to the surface more easily as I'm worried about how stressed he seems.

Does anyone have any suggestions?
 
Hello. The tank is quite small. Even a small amount of dissolved waste material produced by a couple of fish is enough to upset the water chemistry of this tank and stress your fish. Some hardy species of fish can temporarily adapt to less than optimum water conditions, but if they had cleaner, more stable tank water, they'd do much better. A roughly 4 gallon tank needs two or three large water changes a week. You really need a much larger tank if you're going to be successful.

10 Tanks (Now 11)
 
Oh really, the shop I got them from said my size tank should be fine for what I had - should've known better.

So for the three corys and the frog (who is about half the size of my cory) is the tank still too small? What size would be better? (Bearing in mind I don't have ambitions to add loads, I just want my current ones to be okay). I'm a bit pushed for space but if larger is what they need then I'll find a way as I don't want any of my fish to suffer. If I can get a bigger tank, would you recommend more frequent water changes in the current one while I wait for that one to cycle?
 
What species are the cories? The three dwarf species are OK in a tank around 20 inches/50 cm long but the larger cories need more like 24inches/60 cm. With bottom dwelling fish, the floor size is more more important than the volume. Cories also need a large group so a minimum of 60 cm long will allow that - preferably more of the same species of cory you already have.
ADFs are OK in 20 litres/5 gallons but bigger is better. For frogs only, 3 is OK in 20 litres but if you also have fish the tank needs to be bigger.

For both cories and frogs, sand is the best substrate. Frogs can suck up the substrate by accident when feeding and gravel can get stuck. Cories feed by taking a mouthful if sand and sifting the food from it then expelling sand through their gills.


As for cycling, if you move the current filter into a new tank - or 'persuade' the media to fit in the new tank's filter - you can move the fish and frogs over at the same time. Keep an eye on ammonia and nitrite daily until you are sure they stay at zero and do a water change if either reads above zero.
 
Lcc. Corydoras are foragers. They move around the tank looking for uneaten food. So a small tank isn't going to satisfy their need to explore. The average tank keeper isn't prepared to take care of a small tank. They're not up to performing the multiple weekly water changes required to keep a small tank livable for even a small fish. If you're really interested in the water keeping hobby, then give yourself a chance to be successful. If you have any room at all, get a 30 gallon tank and pretty it up for you and your fish. More water means more room and healthier conditions for your fish and really less work and stress for you.

10 Tanks (now 11)
 
What species are the cories? The three dwarf species are OK in a tank around 20 inches/50 cm long but the larger cories need more like 24inches/60 cm. With bottom dwelling fish, the floor size is more more important than the volume. Cories also need a large group so a minimum of 60 cm long will allow that - preferably more of the same species of cory you already have.
ADFs are OK in 20 litres/5 gallons but bigger is better. For frogs only, 3 is OK in 20 litres but if you also have fish the tank needs to be bigger.

For both cories and frogs, sand is the best substrate. Frogs can suck up the substrate by accident when feeding and gravel can get stuck. Cories feed by taking a mouthful if sand and sifting the food from it then expelling sand through their gills.


As for cycling, if you move the current filter into a new tank - or 'persuade' the media to fit in the new tank's filter - you can move the fish and frogs over at the same time. Keep an eye on ammonia and nitrite daily until you are sure they stay at zero and do a water change if either reads above zero.
They are leopard corys, they're about 2 inches long.

For years when I had just the frogs I had no substrate as I'd read they struggled with it, then I got gravel when I got the fish so clearly I'm using the wrong substrate too! I would be transferring the filter/ornaments etc over to any new tank.

Think I need to sort all of this ASAP! Will do some tank shopping at the weekend and see what I can find.
 
Lcc. Corydoras are foragers. They move around the tank looking for uneaten food. So a small tank isn't going to satisfy their need to explore. The average tank keeper isn't prepared to take care of a small tank. They're not up to performing the multiple weekly water changes required to keep a small tank livable for even a small fish. If you're really interested in the water keeping hobby, then give yourself a chance to be successful. If you have any room at all, get a 30 gallon tank and pretty it up for you and your fish. More water means more room and healthier conditions for your fish and really less work and stress for you.

10 Tanks (now 11)
Yeah I feel bad now as it looks like I've not put them in the best conditions through ignorance and they've suffered as a result, I thought that what I'd done was enough but I knew something wasn't right when I couldn't even keep the plants going and lost the two frogs. Just hoping I can remedy before I lose the last one or any of my cories. If I had loads of space I'd have a huge tank but I can definitely do better.
 
Hey Lcc. No worries. Just gradually increase your water changes. Here's a tip: Small tanks need some of the water changed every few days. Work up to the point you change half the tank water a couple of times a week and feed just a little bit of a variety of flakes, pellets and even a little frozen food sometimes. Anything small enough to go into a small tank is going to have a very, very small stomach. So, very little food is needed. You can skip a feeding day once a week. This day, the fish or frogs or whatever will work the bottom of the tank for any piece of food that's left. They'll do their part to keep the tank clean.

10 Tank (now 11)
 
Hey Lcc. No worries. Just gradually increase your water changes. Here's a tip: Small tanks need some of the water changed every few days. Work up to the point you change half the tank water a couple of times a week and feed just a little bit of a variety of flakes, pellets and even a little frozen food sometimes. Anything small enough to go into a small tank is going to have a very, very small stomach. So, very little food is needed. You can skip a feeding day once a week. This day, the fish or frogs or whatever will work the bottom of the tank for any piece of food that's left. They'll do their part to keep the tank clean.

10 Tank (now 11)
I've always fed my frogs in this way, least I'm doing something right! :p

Thinking of ordering this tank, it works out as 128litre capacity whej i calculated it (ad says 112?). Either one should hopefully be plenty.

 
Hi & welcome to start with... :hi:
Well, sufficient remarks have already been given by others about your tank problem. Hope it will help you out...
 
Hi & welcome to start with... :hi:
Well, sufficient remarks have already been given by others about your tank problem. Hope it will help you out...
Thanks, I have really appreciated people's feedback and am taking it on board, seems like a welcoming forum!
 
Hi, I am relatively new here too. Welcome to you. I have been impressed with how helpful people are and there are some really knowledgeable and experienced fish keepers here. The forum is a great resource.
 
I've ordered my new tank and stand, will share some pics as and when I've got it set up and have moved my fish over.
 

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