Tropical_fish's Fishless Cycle - Complete

[OldMan47]

You will need to do a large water change to get rid of the nitrate before stocking with fish. By large I mean you will remove all of the water that you can get with a siphon and replace it with dechlorinated water. You will want your nitrates below 20 ppm before adding any fish.

 

[Tropical_Fish]

Yep that will be coming soon.

Just slightly worried about the dropping pH level.

Tap water is 7.0

After settling in the tank the pH originaly went to 7.9 then settled to 7.6 where it has sat for weeks, but over the last couple of days it droped to 7.0 and now to 6.6

 

[Tropical_Fish]

Hmmmm,

I may have made a mistake.

Just tested the Nitrites and they're still at 0.25ppm (12:00) so that's at 13.5 hours which yesterday it managed to fully process in that time.

The pH had dropped to 7.0 from a stable 7.6 yesterday.

Following that we decided to decorate the tank ready - that involved adding 3 pieces of bogwood which I was slightly worried about as I'd read it naturally lowers the pH. So last night it was 7.0 now it's 6.6.

I'm just worried that the lower pH has slowed the processing?

 

[Tropical_Fish]

Tested at 5.00pm and all the nitrite was gone.

Will re-dose with ammonia at 7.00pm so I can retest in the morning

pH was 6.6

 

[sjolliff]

I used baking soda to bump my PH up and it works a treat mine was at 6.2ish and 6-7 tspn made it go up to 7.8ish (125L tank)

use 1tspn per 20L of water,

at 6.0PH the cycle will stop/stall

 

[Tropical_Fish]

Forgot to redose ammonia last night until 9.00pm,

So re-tested nitrite this morning at 9.00am and I now have a blue test tube - so 0ppm


So it looks like it's there:

Ammonia 0ppm
Nitrite 0ppm
Nitrate - off the scale
pH - 6.6


So I'll just add some ammonia tonight to keep the bacteria alive.

 

[OldMan47]

Dose a few more days once a day and test at 12 hours and you will know whether or not you really have arrived. Meanwhile you should either do a water change or dose up a bit with sodium bicarbonate to get that pH up to 7.0 or more. Your nitrates have probably used up your KH to get that kind of pH drop.

 

[Tropical_Fish]

That makes sense (I think) for the pH dropping. Is it OK to do a water change tonight when I get home from work - and continue dosing to 4ppm once a day - or would I then Need to do another water change on Fri/Sat before the fish go in to remove the nitrate created in between?

 

[Tropical_Fish]

Well I just did a water change, got just about all the water out of the tank but left the filter full - the filter probably holds a fair bit.

All filled back up with a mixture of cold water, boiled water and aqua safe

All switched back on - bit of a blue tinge to the water now from the aqua safe (last time I just used a small bottle of clear dechlorinator but at a couple of quid for a small bottle which only did the tank once - I thought I'd better get a big bottle which would last longer)

All up to temperature now - and will dose up with ammonia at 9.00pm - will take all readings first to make sure nitrate is down

 

[Tropical_Fish]

Just tested following the water change and my results are:

Ammonia - 0ppm
Nitrite - 0ppm
pH - 7.2
Nitrate - Just under 160ppm

So even after a majority water change I've still got far too much Nitrate - It's been off the scale for a good while so I can only assume that it was that high that just the stuff in the filter alone was enough that when diluted still gave a high reading

It's nowhere near as dark as it was but it's still too high.

I'm planning on doing another full change tomorrow - including emptying the water out of the filter I think.

Dosed up to 4ppm with ammonia

 

[jmkgreen]

Keep your filter media in old tank water while you replace the filter water - don't want to see all that good bacteria waste away.

 

[Tropical_Fish]

Keep your filter media in old tank water while you replace the filter water - don't want to see all that good bacteria waste away.

I was going to leave the media in the filter and just tip out the water, I'll have a bucket of dechlorinated warm water next to it and fill the filter back up straight after - so it shouldn't start dying off.




Tested this morning after 11.5 hours and the bacteria is still alive, got zero for both ammonia and nitrite.


Will do the second water change tonight

 

[OldMan47]

Don't stress too much over the small amount of water in the filter, it is probably less than the volume of water in the gravel bed. Keeping the filter media moist is important but I never leave a filter or a tank empty long enough for my media to dry out. When I am doing a filter clean, as I finish with each part, I just stack it beside the sink and leave it there until I put the filter back together. I do not use running water to clean my filter but use the sink to catch all the spills that I have while sloshing the media around in a bucket. My canister does not get refilled before moving back into place, it is designed that way, so the media sits damp for 10 or 15 minutes each cleaning and I have never had that affect the biofilter function of one of my filters.

 

[Tropical_Fish]

When emptying the tank - I got just about all of the water out, I lifted the tank up at one end and put the pipe to the bottom corner under the gravel so it was more or less empty.

The filter probably holds about a gallon or so

 

[Tropical_Fish]

Right - I did a full water change again and did the filter too this time - the filter holds loads of water!

Nitrates now at about 20 (just slightly later so maybe 15-20) which is about the same as my tap water so can't expect much better than that!

Dosed up with ammonia again and will test in the morning at 9.00am to make sure it's still processing in 12 hours. Will then dose again friday night. Then test Saturday Morning. If both tests go well the fish will be going in on Saturday.


Had one slightly worrying moment, I'd obviously taken the filter apart to empty - when I'd put it all back together, and primed it - I switched it on and left it running, tidied up a bit and then noticed that the level of water in the tank had dropped about a cm. The external filter was now sitting in a couple of inches of water! Luckily I keep the filter in a 25L flip top bin next to the sideboard that the tank sits on. Not quite sure which bit wasn't seated properly but I've taken the top off and the pipes off - put it all back together and everything was fine