Pair of A. Hongsloi or Borelii in 35 gal community tank?

[Lemonprophet]

I

You will only need around 5 gallons per water change for the 17 gallon (probably 15 or 14 when full). A 50 gpd unit would be sufficient and di for this species would not be necessary. The bigger issue is the plumbing. I would not buy a pressure tank which can be expensive (though you could); but a 8 gallon pail would be sufficient as long as you remember to turn off a valve before it overflows. Just remember 7 gallon of water weighs aruond 55 lbs.

I was looking at some RO systems for a smaller tank like mine, could you tell me if this would work?

50gpd 3 Stage Compact Reverse Osmosis RO Unit

You are purchasing a high quality Finest Filters 3 stage Compact Reverse Osmosis RO Unit. Complete with all filters and all accessories. This unit comes complete with a 50gpd (gallon per day) membrane. Our quality 3 stage compact RO units come with all accessories required for immediate setup...

www.finest-filters.co.uk

 

[KenL]

Is RO water more likely to have a ph crash that could be an issue?

 

[Lemonprophet]

Is RO water more likely to have a ph crash that could be an issue?

Remineralisation fixes that

 

[Ben Rhau]

It is very difficult for pH to crash even with distilled water, and in fact I’ve never seen it.

 

[MacZ]

Is RO water more likely to have a ph crash that could be an issue?

Not at all.
pH meaures the concentration of free H+ Ions. You would have to add enough to make the pH crash. That can only happen under certain circumstances. Ans just using pure RO and humic substances is not one such circumstance.

I elaborate:
Classic scenario in home aquaria is relatively soft water (< 2°KH) to start with, high stocking density (like... 20 Paracheirodon, 20 Petitella, 15 Hoplisoma and 5 Ancistrus of 7-8cm), no live plants, and 4 full cubes of frozen food daily with waterchanges at best every 3 months.
Nitrogen compounds will rise, nitric acid builds up, the low KH is neutralized while the acid stays... Bam! pH-crash.
Alternatively: For whatever reason you use diluted sulfuric acid to get your pH of your tapwater down to breed a certain fish erroniously thinking that it is exactly and only that factor that will bring you success (Tipp: That alone never does). You make a mistake when calculating the volumes for dilution and accidently put in way too much.

Those are the likeliest situations when the pH in a fish tank might crash. And in those cases you have to be so inept in the hobby, you should better leave it be.

Oherwise it's very unlikely.

 

[anewbie]

Remineralisation fixes that

I think ph crash is a non-issue as long as the ph is below 6 to begin with. I never worry about this mythical ph crash that has polluted the www space. I use pure ro water in 12 or 13 aquarium without known issues.

 

[KenL]

Remineralisation fixes that

So, remineralise RO water? What minerals are added?

 

[MacZ]

So, remineralise RO water? What minerals are added?

The stuff you remove with an RO unit. Basically you re-add GH and/or KH. That's what scapers and underwater-gardeners do for their plants and shrimp, but the fish don't care.

It is cheaper to cut the RO with tapwater instead.

In my opinion once you use RO this is just contradicting the original intention.

Best practice for dwarf cichlids and softwater fish is still 100% RO, no mineral additives, just botanicals, humic substances and maybe some peat (though that's not ecologically sustainable).

 

[anewbie]

I

I was looking at some RO systems for a smaller tank like mine, could you tell me if this would work?

50gpd 3 Stage Compact Reverse Osmosis RO Unit

You are purchasing a high quality Finest Filters 3 stage Compact Reverse Osmosis RO Unit. Complete with all filters and all accessories. This unit comes complete with a 50gpd (gallon per day) membrane. Our quality 3 stage compact RO units come with all accessories required for immediate setup...

www.finest-filters.co.uk

It should be fine for borelli; for a more sensitive species that is wc you might need di stage; the quality of the ro system depends on the membrane used as well as the sentiment filter - unfortunately i don't really see any details on what that unit uses though in all honestly borelli are not super sensitive so i would go with the least expensive unit you can find.

 

[MacZ]

The product numbers of that unit add up. The insides of all quality RO units in the EU and UK are manufactured by one of only three companies. Vontron, which they sell, is one of them. It's going to do its job well.