Our new plan to avoid fluctuating CO2 sadly had to be put on pause.
I discovered a bacterial infection on one of my corys, and upon testing the water (yes i know, tests), found that there was a reading of 0,025 - 0,05 nitrite. I assume that the transfer of the complete filter media from the old Eheim to the new Aquael was too big of a change for the bacteria and thus I had a spike without me knowing. That is, until one of the fish got sick. Shame on me for not testing daily after such a change to make sure everything went ok. But if I learn from it then it is not all negative.
Ive been doing daily 50% water changes and the fish has now fully recovered without any medication.
There are still slight readings for nitrite, so I will continue with the daily water changes until the filter is back on its feet.
Whilst contravetial on here... you might also like to try a siesta lighting regime to try and maximise available co2 during lights on periods. George Farmer is also currently giving this a go as per his YouTube.
I read a bit about the siesta method before, it does seem like a highly disputed subject. Havent really seen anyone showing great results either positive or negative for it. I am personally unsure if I think that the plants will actually rest during the dark siesta. How long do they need to become inactive, and how long again to be active after this rest period. And wouldnt the algae be better at dealing with this sort of fast flip flopping. I dont know.
I'm very confused how
Seachem Matrix which is apparently a biological filter media claims it is going to control nitrates. Last time I checked the nitrogen cycle produced nitrates (which of course your plants need!).
Your setup sounds good. Can we see a full tank shot? Check flow is getting to whole tank (2000 lph is enough on paper for 180l), keep up with the reduced light - some combo of 6 hours, no reflector, old tubes, floating plants, raise the height above water.
If you get stuck you could try daily dosing liquid carbon (Easylife EasyCarbo or Seachem Excel) - it will annoy the algae and should give the plants a boost IF there is too much light for the available CO2. Caveat, so long as you're not growing vallisneria.
Seachem claims that the bits of Matrix are deep enough to have anerobic cores, who knows if this is actually the case. Either way, its unlikely to be some sort of magical bogeyman that I can blame for all my troubles.
Full tank shot attached, its not exactly where I want to have it, to say the least, but it is in progress. Still waiting to get more plants. Photos taken right after water change, so please excuse the bubbles.
I have a spray bar running the back length of the tank, and the flow is a fair bit more than most low tech tanks, I am confident enough to say. If I squeeze any more pressure from the spray bar, the fish food gets blasted into oblivion immediately, the shrimp look like they are in a wind tunnel when they cross the sandy areas, and the plants start "whipping" more than waving in the flow. The fish can deal with even higher flow, but for those three reasons I am wanting to keep the flow at this level. Its a "good swirl all around" and all the plants are moving. There is slightly less movement in the back left corner, partially because this spraybar that I am using right now has uneven pressure and jets that dont go perfectly straight, especially at the start of the bar. I am gathering materials to make a custom one at the moment, and hope to be able to get straight jets and even pressure all along. Another reason is the density of the bolbitis and the h. difformis breaking up some of the flow in that area.
The light is currently running at only one out of two bulbs, and very annoyingly to me, only 6 hours a day. The bulbs were replaced at the start of my journal so they are no longer old, but the reflector is still gone, and it doesnt look like I should replace that any time soon.
I am in a war with the honey gouramis over the floating plants. The female gourami, less affectionately named Miss Piggy, insists on eating off all the roots of the floating plants. Obviously the plants are not super happy about this, and coupled with the high flow in the tank they are having a -very- bad month.
Ive been having trouble keeping the plants contained in one corner when the little fat blahblahblahblahblahblahblah keeps eating the roots off and making them float out into the tank, to get bashed around by the spray bar and submerged to the point where the air coating of the salvinia leaves are destroyed, and then the leaf dies. I have two and a half small plants left at this point. I have made prototype number 532 of the floating plant containment corner, and it looks like this one is actually effective enough. Its made of stiff black plastic mesh attached to two suction cups with thread, and it goes both above the water surface and a bit below, to keep them in even when the water level drops a bit due to evaporation. I am taking them out and putting them in a small cup temporarily during the water changes, so that they dont get bashed around any more.
I dont really want to dose liquid carbon, it takes my tank in the wrong direction in relation to what I want.
I want to keep things simple and preferably in the direction of less fiddling and adding and mucking about, rather than more complicated. I also have concerns regarding adding ""some unknown chemical"" that we dont know exactly what does, into our tanks full of critters. I am growing a bit of vallisneria, not very well may I add, but I would like to give it a good go before I give up on it. I might have too soft water for it.
All in all the plants are still doing alright, its not perfect but it sure isnt a disaster either.
Getting some thread algae and some older leaves getting coated in algae still.
Most of the plants are growing just fine, the rotala has unstunted slightly, its not super happy but its not dying either. The hygrophila difformis is healthy enough that I can take off the top shoots to make it branch without issue, and the one new plant I got my hands on is growing very well. Its heteranthera zosterifolia, and it made the transition from tissue culture cup to my tank without missing a beat. Very pleased about this. I need more bushy plants to grow well so I can start covering up the back wall. Tank looks much too bare for me right now.
Talk about being a lazy fishkeeper 
