When to add additional fish?

FishForums.net Pet of the Month
🐶 POTM Poll is Open! 🦎 Click here to Vote! 🐰

Newfish21

New Member
Joined
Mar 16, 2023
Messages
4
Reaction score
0
Location
UK
Hello,

I have had a new 40 l tank for about a month. It originally had 6 cherry barbs (3 male 3 female) and after 2 weeks 3 panda corys were introduced, along with a zebra snail. A few days after the corys were introduced, the 3 female barbs died. I think they had been affected by fluctuations in water parameters as they had no visible signs of disease or anything. I have been adding a filter boost and using seachem prime when ammonia levels were a bit high, and have been testing the water daily and now it seems to have levelled off to everything being at safe levels on the test strips. Is it safe to add further fish now or should I wait longer? When i do, should get some replacement female cherry barbs or go for a different species? Thanks!
 
Well......it sounds like you have an uncycled and overstocked aquarium...perhaps

40 litres is not very big and it can take anything over and above 8 weeks without fish and 12 weeks with fish to fully cycle a new aquarium

You may have added too many fish too fast into an uncycled and potentially too small for that fish number aquarium.

Can you elaborate on how you set the aquarium up from getting it out of the box, your full water chemistry (available from your water supplier website - just enter postcode), your weekly maintenance routine please?

There shouldn't be any ammonia at all as that is poisonous to fish. Having relatively high numbers of fish in a smaller aquarium will produce higher ammonia due to fish waste and any leftover food etc.

A photo of the full aquarium would also be handy too along with your most recent test results. Using Prime or any other ammonia block/control will stall the initial cycle. Prime is an effective water conditioner for use on water changes to negate chlorine, it shouldn't be used to control ammonia.
 
Hello

Thanks for replying. It is very confusing when first starting out as all the advice seems to vary. I followed the advice given when purchasing the tank (they said it would be fine for up to 12 small fish), and i have since been made aware that they probably shouldnt have sold me six fish at once to start the tank, but now that i have them i am trying to do the best i can with what i have.....
The water chemistry is

1678962801845.png


I set up the aquarium as advised by the fish shop i purchased it from. Cleaned it first (using no chemicals), added aquarium sand as a base, with 2 living plants on wood and a moss ball and a couple of cave type ornaments. I put the water in, added the correct dose of prime and the correct dose of filter boost and turned on the filter and heater. The shop told me to leave it 3 days before adding fish, which is did. I also continued to add the filter boost as directed for new tanks on the back of the bottle. I went back to the shop and they advised to buy 6 cherry barbs as they wouldn't like being in a smaller group than that. They said new fish could be added in a further 2 weeks, and advised the panda corys as a suitable tank mate. It was only a few days after getting the barbs that i found out about ammonia levels - i had been testing the water using the test strips with nitrates/nitrates/ph etc on them. When i purchased some ammonia test strips and tested the levels were too high, so i did a 25% water change and added prime (the back of the bottle said it could be used as a water conditioner and to control ammonia, so this seemed the correct thing to do). The levels of everything seemed low and stable for the next few days. I went back to the shop and told them this, and they said that it was fine to add the new fish if the water parameters were ok now, which they were. So they sold me the 3 panda corys and the snail, and i introduced them to the tank. i continued to monitor the levels and the ammonia rose slightly again, so i added the prime, following the instructions on the back of the bottle. The levels then fell, but a couple of days later the 3 female barbs had died. That was a week ago. The male barbs and the corys seem fine and active in the tank. The test strips i took this morning had the ammonia as being pale yellow, with the levels of all the things on the 7 test strip all being in the "safe" sections of the strips.
 
It definitely seems to be a case of storeperson giving poor advice (it happens alot, so don't kick yourself over it)

Your aquarium is around 10 US gallons (forums generally stick with the US gallon since getting stock or dealing with water chemistry and other additives tend to be per US gallon)

Three days from setting up to adding fish is absolutely bad advice, I am sorry but whoever advised that really didn't know enough to tell you anything.

Have a good read of the advice given on this link....


It will really help you get to grips with your aquarium and how to get it sorted properly. I shall tag @Essjay, @GaryE and @AdoraBelle Dearheart to drop by on this thread to advise you too...and others will likely come offer help too.

You really need to match your water chemistry to fish.......unfortunately fish cannot adapt as well as people think....they are pretty specific on hardness, pH etc which is why the water company report is valuable before going out to buy fish and only get fish that can handle your tap water and thrive. The wrong water can shorten the life of fish, cause health issues with them, so it is quite vital that you know your water.

When adding Prime specifically, it needs to be shaken vigorously before adding the dose to the water being put into the aquarium. Prime should only be used when doing water changes, the bottle might well say that it can cut ammonia, but infact it only alters it into a semi non toxic version and it can be troublesome especially in uncycled aquariums where ammonia is actually needed in order to kickstart the good bacteria that lives inside the filter and on substrate/decor which acts as a natural ammonia eater.

Until your aquarium is fully sorted I would not be getting any further fish. The fluctuations in ammonia are likely to continue so you should ready yourself to lose more fish, Cories are very susceptable to water chemistry issues. Doing a fish-in-cycle frequently costs the lives of fish....its why most people prefer to get the cycle done without them.

Have a good read of the link above, ask any questions you have...don't be afraid to ask anything if you are unsure. In the meantime, you might consider getting a liquid testing kit...more expensive than paper but tends to be more accurate than paper, especially in the very early stages of aquarium set up.
 
Thanks - thats really helpful! The article looks really useful - and it is correct, the fish store didn't tell me about cycling!

How many fish would you recommend for this tank once it is sorted? Would it be best for the male barbs (hopefully if some make it) to have females with them?
 
Thanks - thats really helpful! The article looks really useful - and it is correct, the fish store didn't tell me about cycling!

How many fish would you recommend for this tank once it is sorted? Would it be best for the male barbs (hopefully if some make it) to have females with them?
Cherry Barbs might not be your best choice.

Personally I have never owned Barbs....but 10 gallons seems on the small side for what you are hoping for.....although a small variant, the Cherry does still need a decent amount of volume to thrive (20-25 gallons plus maybe) and a decent shoal of 6-8 or more to curb any temperment issues and to give them security. As to the water chemistry being suitable I shall leave that to someone with experience of Cherries to discuss with you.

@Byron @Wills should be able to assist you with that part of the equation more than I can.
 
The good news is that you did get fish suited to your water. The table gives your hardness as 8.26 deg Clark. That unit isn't used in fish keeping so we need to convert it into the two which are used.
Your hardness is 118 ppm and 6.6 dH. UK water companies always make water sound harder than it really is - yours isn't slightly hard at all, it's soft.

Can you tell us the dimensions of the tank, please. We know the volume is 40 litres, or 10 US gallons, but small tanks in the UK tend to to be taller and narrower than those of the same volume in the US - knowing the dimensions will help members from all countries to suggest suitable fish. The swimming length of the tank is more important than the volume.

The best website for researching fish is Seriously Fish. For example, they give the minimum tank size for cherry barbs as 30 x 60 cm footprint (12 x 24 inches)


Your first need is to get the tank through the cycle. If possible, take the fish back to the shop and do a fishless cycle. If this is not possible, get some live plants. Elodea is cheap, sold almost everywhere and can be left floating in the water. Plants take up ammonia as fertiliser and they don't turn it into nitrite.
Please don't get any more fish until the tank is cycled, but we can discuss which fish would be suitable for the tank size and your tap water during this time.


One final thing - as you have already discovered, fish shop workers do not give good advice. Don't let them advise you about suitable fish, ask here instead :)
 
All good advice - thanks!

After reading the articles above i am still slightly confused as to how i will be able to tell when the tank is successfully cycled?
 
It depends on whether there are fish in the tank or not.

Fish in - when both ammonia and nitrite read zero for seven consecutive days when no water changes are needed to be done.

Before adding fish (fishless cycle) - when a 3 ppm dose of ammonia is cleared to zero ammonia and zero nitrite within 24 hours.


With fish-in cycling, the tank is cycled for the amount of fish in the tank at that time. Adding more fish means adding more ammonia (fish waste) so the bacteria have to catch up. Adding too many fish as soon as the cycle has finished can mean ammonia and/or nitrite in the water for several days, so it is better to add new fish a few at a time.
 
Listen to @Essjay. I will just mention that you need to re-think the fish once the tank is cycled and ready. Barbs are by nature active fish which means more space (length and width is more important than volume). I wouldnot get more, and I would see if the store will take the barbs back. To be at their best, you need 10 or more, and this is too small a tank.

There are small fish, often called nano fish, and most of these are well suited to your soft water, so there is plenty of options going forward. We can discuss these later.

The panda cories would be better in a larger space, but they can manage here. But, they need a group of 8-9 (or more). And they must have a softy sand substrate. You have the option of providing what they must have, or returning them. Again, there are a lot of fish species that would be fine in this sized tank. You/we need to ensure what these need is available if they are to bee healthy.
 

Most reactions

trending

Staff online

Back
Top