Fishless Cycling Problem

You fix a deficiency in hydrogen ions by adding acid  I once came across an experienced fishkeeper who said he used muriatic acid to lower pH. I had no idea what that was so I googled it - it's the old name for hydrochloric acid  I would prefer to use a weaker acid than that.

Looks like I will have to go the fish in route. Thinking of using 4 Harlequin Rasboras in my tank, 105 litres. Does that sound right and any other tip for fish in cycle?

I wonder if the ammonia is being converted to ammonium?  What's the implication of not enough hydrogen ions in the aquarium?  How would you fix it?  I've looked into the chemistry aspect of it but would need more time to make sense of it.  Is this even a possibility caused by the low kH?

I have just paid proper attention to this post. Ammonia is converted to ammonium when there are lots of hydrogen ions, ie the pH is lower than 7. The filter bacteria grow best at a pH above 7, ie when there are less hydrogen ions so more ammonia is in the ammonia form rather than ammonium. This is why adding sodium hydrogen carbonate (bicarbonate of soda) works during cycling. It is the salt of a weak acid and a strong base so it makes the water more basic - that is, it increases the pH. And it boosts the KH.

Good luck and please keep us posted on progress.

I'm keeping my fingers crossed for you and your fish. 

Glad the fish are settling in well so far. I wasn't aware of the advice not to water change for 14 days until I "googled" and found a post on another forum which includes a reply from Tetra staff and mentions this and not using anything which detoxifies ammonia (Seachem Prime is one such product). When I struggled with a fishless cycle myself (using fish food as the ammonia source and Tetra Safestart), back in the days before joining this forum, I resorted to a fish-in cycle and continued using Tetra Safestart, twice-daily monitoring of water quality (ammonia, nitrite, nitrates, etc), daily water changes using Seachem Prime, etc. I'm almost certain we had a user on this forum last year who did the same, so this is news to me.

I would monitor the water quality morning and evening and let us know how you're getting on, so that we can advise further if need be.

Do you, by any chance, have any mature media from another fishkeeper? That would speed up the cycle considerably.

Best of luck.

Water checked today, .25ppm ammonia, 0 nitrites and 2.5ppm nitrates(same as tap). Did feed yesterday, didn't put a lot in, how often should I feed 4 fish? I think only 1 small bit got to the bottom.

I'm happy to provide mature media. 

Great - hopefully we'll get you (or your filter, more precisely!) cycled very quickly this way.

You could either remove (cut out) some of the sponge or, preferably, just squeeze in the extra sponge/foam which we send you. I have a few tatty pieces too, so pieces of those could actually be squashed in nicely in various locations alongside your existing sponges, hopefully covering more of your existing sponge's surface area and transferring beneficial bacteria accordingly than if you just pushed in one large chunk of filter media.

I brought some Hikari mini pellets today, do you think 8 pellets each feed is enough? I have 4 fish.