Care and maintenance for an older tank

[beanbag]

Hello folks,

This question is regarding my other shrimp tank, which is 10 months old now and 2.5 gallon.  It only has two amanos and one blue bolt who is as old as the tank plus however old it was when I bought it.  (I used to have more shrimp, but they died off due to overfeeding and water pollution)  The Amanos seems to be doing fine and generally appear well fed, but less lively.  The blue bolt seems to be slowing down and spends most of its time standing around or slowly digging thru the substrate.  I'm not sure if this is just due to old age, or over / under feeding or unbalanced diet.  A few other things things:

Water parameters still test OK.  I can't ever get finite nitrate readings even when dosing a little all-in-one fertilizer.  PH is upper 6's, which is higher than my newer tank that uses the same water and substrate.  (Oh, maybe substrate is getting depleted?) GH=5-6, but there is a little more "extra" TDS over the the TDS of my input water.  (OK, this might be due to ferts)

The moss tree is overgrown and now there is a big clump of moss in the center that blocks a lot of the light.

Some floating plants.

15% water change once every 1-2 weeks, but I haven't been doing any gravel vac.

The Dwarf hairgrass is yellowing and slowly dying off in areas.  Sometimes it is because the shrimp dig it up and chew at the roots, or maybe it isn't getting enough light?

I use to feed the shrimp every 3 days, but now that interval has been getting longer.  Even if I haven't fed them for 5 days, they still don't care to come out for the food.

I think maybe the "plants are winning"(?) because there used to be biofilm growth on the front glass and now there isn't any more?  Nitrates are always at zero and there doesn't appear to be much algae growth.

I wonder if I should do some moss trimming and floating plant removal, or maybe gravel vac, or just leave things alone?

Edited December 7, 2019 by beanbag

[sdlTBfanUK]

It sounds like this tank is doing well which is good, I think shrimp only live 1.5 years (except amanos which are 5 years) so the blue bolt is probably nearing the end.

From what I have read over the years, it is best to keep on top of trimming plants when you do each routine maintenance rather than do a big trim as that can cause an imbalance which can be disastrous, so I would trim it but only a bit each time until you get to where you want it!

I'm not sure what the substrate is you have but I doubt you can gravel vac soil substrate very well anyway, I would maybe get a couple of snails?

There are a few grasses that do much better with CO2 so hairgrass may be one of those, but if the shrimps disturb it anyway it  would probably be best and easiest to try some other plant. Maybe the extra moss from the tree you could make a moss pad?

You could add any cull shrimps from other tanks to this tank when you get to that stage?

Simon

[beanbag]

1 hour ago, sdlTBfanUK said:

I'm not sure what the substrate is you have but I doubt you can gravel vac soil substrate very well anyway, I would maybe get a couple of snails?

I forgot to mention I use UNS controsoi, which is little balls around 2mm in size.  It probably grows a layer of biofilm because all my shirmp like to graze on it and roll the little grains over to pick at all side of it.  It is very easy to gravel vac and usually removes a bit of "mulm" (I think it's called that?) .