Advice Wanted On Setting Up A Fresh Tank

Hi there   

If it has only been a few week then there is a possibility that the bacteria in the old filter are only dormant, and not dead, so using the media from the filter to seed the new filter will speed up the process.

Then follow the sticky describing fishless cycling https://forums.thinkfish.co.uk/fishtank-filtration-and-cycling/fishless-cycling-how-to-do-it/ to make sure that you have enough bacteria prior to adding fish.

Hope it all goes well and that you keep us updated on progress. 

As a matter of idle curiosity, what were the issues with the light on the old tank? I have an Aqua One AquaSpace (described as 32 litres but actually holds 26) and that came with a clip on LED. I unplugged it a year or two ago and the transformer-plug came apart in my hands. I replaced it with Hiddom light!

It was a fluorescent light in a sealed plastic case but it appeared that water was getting on the inside. In the summer my husband replaced the light and thankfully was in the room at the time as the light almost immediately started flashing. My husband turned it off but said that the whole fitting was very hot indeed. We carefully tried another light in case it was a faulty bulb but had the same result. As the tank is bright pink and is not generally looking so great and the hood is discoloured on the inside likely due to an overheating light we decided a new tank was the safer option as it is in my 14 year olds bedroom.

Hi there   



Then follow the sticky describing fishless cycling https://forums.thinkfish.co.uk/fishtank-filtration-and-cycling/fishless-cycling-how-to-do-it/ to make sure that you have enough bacteria prior to adding fish.

Hope it all goes well and that you keep us updated on progress. 

Am considering careful fish in cycling this time ... The fishless only got us so far last time. Preferring to grow bacteria on media and then slowly add fish. I do have all the relevant test kits! 

It strikes me that if you used something like a ceramic media instead of sponge then this issue would not present itself... I have seen one of these filters used before, it was filled with plants doing natural filtration as part of a dissertation.  Quite impressive!

Sounds like the old media worked well.


How big is the tank? Just a word of caution that 6 female bettas will need quite a large, heavily planted (real or fake) tank. Some girls can be even nastier than males so they need space to get away from each other and lots of places to hide.

Hi Dawn,

Glad the fish are doing well so far. How is the water quality (ammonia, nitrite and nitrate levels)? Test the water before your usual/scheduled water change - ammonia and nitrite should be at 0 and nitrates no more than 20 above whatever your tap water level is. That should help give an indication of how the filter is doing, either giving you peace of mind (if your levels are as described) or else suggesting that you need to increase the frequency and size of water changes (if higher than the figures I've given) or even potentially considering a larger tank to house your existing stock if it's difficult to keep water quality at the safe level. Splitting the fish between the existing tank and a second small tank doesn't seem to be a feasible option - female bettas need to be in groups of 4+ as described in this thread https://forums.thinkfish.co.uk/new-fishkeepers/given-a-siamese-fighting-fish/

Shops do tend to overcrowd fish, either selling betta in very small environments or cramming lots of fish into a tank, as they know that the environment is only temporary. I would suggest keeping to the 4 that you have as you are actually overstocked already for the size of the tank. You might find these articles useful http://www.thinkfish.co.uk/article/siamese-fighting-fish-betta-splendens, http://www.thinkfish.co.uk/fish/siamese-fighting-fish-female.html and http://www.seriouslyfish.com/species/betta-splendens/

Hope that's helpful. 

I have checked with someone I know who has had betta sororities for years. He says that 4 is the minimum number of females, and that number needs a tank 60 cm long at the minimum. 30 litres is too small for a sorority.
4 females in 30 litres is a ticking time bomb.

If it was a shop that told you, you need to be aware that most of them will say any rubbish to make a sale. Never believe anything a shop says; always research for yourself.