Resurrected Freshwater Tank Ph Very Low & Ammonia Problem

Also. Please lend us your level headed brain on these questions sfsamm

1. Should I buy SeaChem stability?

2. Given the bio load is so low in our 165L, I feel like we may need a few small fish. Stocking plan includes +\- 8 kuhlI loaches. But that means we were gonna move gravel from a third of the tank and put in sand we bought. Should we...

A. Wait, do nothing but monitor & let tank settle, or

B. Get half the loaches & add them without sand now to increase bio load & feed bacteria, or

C. Go ahead with the sand plan now given we've stirred something up already might as well?

(Note: kuhlI loaches do best in water that's a month old and ours is barely 2 weeks. )

3. Given the low bio load, we could transfer the 6 rummy nose to our 165L tank once the new "tannin" tank arrives tonight. But! That would leave the tannin tank with no bio load for its 4 year established BB ... hence I think that's a mistake?

I'm over thinking all this because we're spending hours re painting our daughter's room the past 2 days & every time we go to the kitchen to wash up the rainbows come right up to the front of the tank looking curious & wanting interaction lolz

 

1. Should I buy SeaChem stability?

I keep some on hand, I find it handy. It definitely doesn't hurt anything to use it and depending who you ask opinions on bottled bacteria vary... Personally I like Stability, I use it when I'm doing something that could disrupt a tank in a big way. Like when I add new fish, do a major remodel, pull up or add a bunch of plants, etc. It makes transitions smoother in my experience. I don't necessarily think it should be leaned on as a sole source of stabilizing a tank but a crutch, sure, I like a helping hand and stability has always either done nothing and I'm super lucky or has kept things mostly in line lol.

2. Given the bio load is so low in our 165L, I feel like we may need a few small fish. Stocking plan includes +\- 8 kuhlI loaches. But that means we were gonna move gravel from a third of the tank and put in sand we bought. Should we...

A. Wait, do nothing but monitor & let tank settle, or

B. Get half the loaches & add them without sand now to increase bio load & feed bacteria, or

C. Go ahead with the sand plan now given we've stirred something up already might as well?

(Note: kuhlI loaches do best in water that's a month old and ours is barely 2 weeks. )

3. Given the low bio load, we could transfer the 6 rummy nose to our 165L tank once the new "tannin" tank arrives tonight. But! That would leave the tannin tank with no bio load for its 4 year established BB ... hence I think that's a mistake?

There's no right or wrong way. Loaches yes like sand, rough or sharp gravel can injure them, smooth gravel though not ideal would work.

SOOOooo, myself I would YouTube the bottle method of adding sand to an existing tank with water and fish (works pretty well when I tried it last summer). After you're ready I'd move over substrate, make it a bit deeper and leave most of it in the tank just have a deeper gravel bed and then I'd add the sand where you want it. If you dislike the look of deeper substrate you can remove it a few scoops at a time during water changes.
Let the tank settle a week or so, be sure you don't have any big spikes and let them settle out if you do. Then I'd add half th khulis wait a couple weeks for everything to settle and then add the last few khulis. Myself I'd use stability for a week after substrate moving wait a few days to be sure it's solid on its own. Add khulis, watch for test readings and start dosing prime and stability daily for a week and hopefully it will be almost caught up by 7 days. Wait a week or so after everything stays solid no spikes and add rest of the khulis again 7 days stability and prime as soon as you see readings.

Khulis are sensitive to Ammonia and nitrIte a bit more so than a lot of fish, but they are far from super sensitive. If you keep prime and stability every 24 hours, don't let your Ammonia and nitrIte total over 1ppm, and keep up with maintenance you should not have a problem.

I'd absolutely not add the new tetras from the new tank to your tank. You have two projects and until they are both stable, solid and adjusted I wouldn't dare combine them. That opening the door to a whole host of issues. Lol right now you know exactly where you are on this tank and have a good idea on the other lol keep it simple let's not go mixing up projects and getting other things involved just yet. Patience.