Cycling My Second Hand 240l Fish Tank

[simonandlisa]

hi everyone im new here nice to meet you all.
me and my girlfriend have bought a second hand juwel rio 240 litre tank, when we bought it this tank was full of algae so we had to scrub the tank and and couldnt use any of the water due to it was green lol. now what we have done is bought a fluval 305 external filter and also still useing the juwel filter at the same time so twice the filtration, which is a good thing, we started the water cycle two week ago, now please bear in mind three fish came with the tank which is a clown loach a pleco and a bala shark, which i know isnt good fish for cycling a tank, but we are keeping a good eye on them.
on the first week we tested the tank for ammonia and nitrite which was all 0.0 on the nineth day we had an ammonia spike of 0.04ppm but we had to reduce that due to fish in the tank so we bought nitra zorb which done a great job in two days no ammonia no nitrite but loads of nitrate, so we have taken the nitra zorb out and put clearmax in the fluval, the temp of the tank is 78f, we did put nutrafin cycle in water also aqua safe and stress coat. but what i cant understand is why did the cycle take so quick to mature.
last night we had a nitrate reading of 70 mg/l so we done a 30% water change and also added aqua safe and nutrafin cycle and stress coat and the nitrate has now dropped to 50 mg/l but this is still high,
can anyone please tell me why the cycle matured so quickly, also why nitrate is still high, we feed our three fish ever other day but we are very careful not to over feed them,
also as we have changed test kits, the first was reading in ppm but the new ones we have bought read in mg/l could anyone expain if there is a difference between ppm and mg/l
many thanks

 

[thomasp9021]

you said the tank was full of algae but i bet the bacteria were still alive on the sponges in the jewel filter.

 

[simonandlisa]

you said the tank was full of algae but i bet the bacteria were still alive on the sponges in the jewel filter.

hi, sorry what i didnt tell you was i ran the juwel sponges briefly under the tap to get algae off

 

[OldMan47]

Welcome to the site Simon and Lisa. Although you don't want any ammonia or nitrites in your tank, you also do not want to use the Nitra-sorb in the tank. The problem is simple to explain. You have a filter that is trying to develop a bacterial culture that processes ammonia and nitrites to make the end product of nitrates. The bacteria need the ammonia and nitrites as their food source. By removing the ammonia chemically, you starve the bacteria. So far that would not be a problem for the fish but when the chemical treatment runs out, there will be no bacteria to deal with the ammonia and the fish will be severely impacted. It is best to avoid using such products because you don't want to end up totally dependent on them for the fish's survival. Instead, it is best to do large partial water changes when levels get too high and allow the bacterial colonies to develop instead. That way you will get to the point that the bacteria can take care of all of the ammonia produced.
Chemical additions to the tank water should not be done. If you have a water problem, change more water. The expected result of a water change can be calculated if you know both the tank water reading and the tap water reading for a particular contaminant by using simple ratios. As far as I know, Aquasafe and Stress coat are both dechlorinators. Only one of the dechlorinators need be added during a water change but dechlorinators cannot substitute for water changes. Your cycle has not matured yet but is probably nearing an end based on having a mature filter that was not allowed to dry out.

 

[simonandlisa]

hi, thanks for the reply we have taken the nitro zorb out but replaced it with clear max which i put in the external filter so should i take that out and just do water changes if levels go up but the problem what we have now is nitrate which is 50 mg/l after a 30% water change many thanks

 

[OldMan47]

Nitrates at 50mg/l is not a real problem. It is a bit higher than we generally like but will not harm most fish. Just keep close watch on your ammonia and nitrite levels and do as big a change as it takes to keep both at less than 0.25 ppm. There is no 30% limit on the size of a water change. If conditions warrant, you can do a 90% change provided you match temperatures and use a good dechlorinator.

 

[waterdrop]

Yes, and in fact I'd guess larger percentage water changes, done with good deep gravel-cleaning would help drop those nitrate levels a bit while of course helping continue keeping ammonia, nitrite at 0,0 for the fish-in cycle. Not sure about the ClearMax as the only thing I've seen by that name is a Fluval product that says it clears nitrite and nitrate but is mainly aimed at removing phosphate, which would make it more of a chemical media and not what we'd really want to recommend for the main standard filter, but perhaps that could be discussed a bit.

I think from reading this that the Juwel sponges may have been mature enough that a pretty good bacterial population survived the chlorinated tap water washing and that would be why this fish-in cycle is not at the very beginning.

~~waterdrop~~

 

[simonandlisa]

hi,
thanks for the help and great advice,
so far, as things stand, we have taken the clear max out of the fluval and replaced that with the fluval biomax, and performed a 50% water change today to try get the nitrate down,
also we have tested our tap water for nitrate and found that it was about 20 mg/l, ( filled a glass and left it over night before testing )
when the ammonia spikes again how high should we let it go before doing a water change as we have fish in the tank, and how much and how often should we do a water change
many thanks

 

[waterdrop]

Wonderful! We've now about worked you around to the rough start of a standard Fish-In cycling situation, which at least is better than having the other complications you had!

Now you can probably look at OM47's sig and click on the fish-in cycling link (or perhaps there are other ones around) and begin to get this process learned and going.

Your main goal in fish-in cycling is to be a sort of detective and figure out what percentage and frequency of water changes will get ammonia and nitrite(NO2) down as close to zero readings as possible and letting them only ever hit 0.25ppm (yes, 0.25ppm for both ammonia and nitrite(NO2).) Usually we start people at 50% water changes daily and then from there they can start to figure out if they can get by with less or need more.

Its important of course to use good water changing technique, with 1.0, 1.5 or up to 2.0x (times) dosing of a good conditioner like Seachem Prime or other product that removes chlorine/chloramine. The temperature also needs to be roughly matched (using your hand is good enough). Those two precautions, which are not necessarily so important in a long established tank, are quite important I believe in tanks with fragile beginning bacterial populations you are trying to encourage to grow.

Hopefully with a big tank like that you are using some sort of long hose system to make water changes easier.

~~waterdrop~~

 

[simonandlisa]

Hi, ammonia and nitite are zero, nitrate is high, but levels in our tap water are,
you refer to levels not going above 0.25 for ammonia and nitrite but we have nutrafin test kits and on the ammonia result card it goes up in stages of 0, 0.6, 1.2, 2.4, 4.9 and 7.3, mg/l so when you say 0.25 would that be between the 0 and 0.6 or the 2.4 reading, sorry if this sounds daft but the first 2 readings on the result card are so very close together in colour,
thanks again for your advice and help,

 

[waterdrop]

Yes, 0.25ppm would be some color halfway between 0 and 0.6ppm on the Nutrafin kit. We tend to use the numbers from the API kit which most of us use. Its a very small amount. If the Nutrafin kit is only sensitive enough to seem to jump straight to the .6 reading then you'll just have to use that.

~~waterdrop~~

 

[simonandlisa]

Hi waterdrop,
thanks for your advice and help, we will invest in a more accurate testing kit, for now its just test and wait for ammonia to rise,

 

[waterdrop]

The Nutrafin Mini-Master Test Kit is one of the ones that have been reported to be ok by our members, so I'm sure you could get by on it if you don't want to invest in another one. With only 3 fish (?) in a large tank it may be a while before you detect ammonia. Most people perform morning and evening tests (or whatever 2 points of the day work for you as long as they are consistent) during either type of cycling. You could probably get by with just ammoia for now, although I'd do a nitrite every couple of days just so it didn't surprise you, but its more likely the ammonia would show up first, prompting you to do the other also. The pH test should also be done, probably once a day.

~~waterdrop~~

 

[simonandlisa]

Hi all,
just an update, aquarium ammonia and nitrite both zero mg/l
worried about our tap water though, nitrate is reading 75-100 mg/l and ph is 8 approx
also does anyone know about detonators for nitrate removal ??? do they work as they are very expensive???
thanks
simon and lisa

 

[Miss Wiggle]

just to answer a question above that wasn't answered, mg/l and ppm are exactly the same so no need to worry over that.

water changes are all you need to remove nitrate, no point using checmicals to do it.

theres evidence to show that most tropical community fish dont suffer until you get to 400ppm or even 1000ppm so don't panic over 100ppm, some people even have 40ppm out of the tap and manage fine.

just aim to keep it no more than 20ppm higher than the level from your tap.

just do some large water changes and it'll come down.