The point of dark pools is to have a private transaction, I don't know the ratio between day trades and long term trades within a dark pool - but looking back in history, yes, block trades were used as long term holds, I doubt that is the case now. How traders can use dark pools now is that its the next ECN that is used after public ECN availability has been depleted. If you live in the USA I'm sure Robert can give you better options with lightspeed vs IB and if you live outside of US I can give you a few suggestions to reduce costs and find better routes.
I can't discuss my business relationships publicly and I don't feel comfortable asking your private trading details publicly either, since some trading firms don't accept certain EU countries that are sanctioned. Feel free to DM me.
In the U.S., probably nothing faster than Lightspeed for stock daytrading. I'm basing this off of seeing Ross Cameron's fills carrying 15K-40K positions at a time in very fast moving small cap stocks. You can see his live trading on his YouTube Channel. [Disclaimer: not affiliated with the dude, haven't given him 1 penny]
I traded RRR, TPR, BLMN with a sell order 50,000, 40,000, and 30,000 shares all or none limit orders at current best bid during mid day when market is slow trading 10 to 3000 shares. I see from time sales the previous orders were small lots. But my orders hit the market , it was able to fill right away without move the market. I talked to an agent. If I use a market and limit order, it may be different n move the supply / demand. Hope this help
That's not possible Buy at bid, sell at ask You can place your order, but u just wait till market move to your price. I tired that many times Only the best bid move to your ask, u sell and Only the best ask move to your bid, u buy I accumulated shares day ahead, not day trade. I bought at market prices, 100, 500, 1000 to 5000 shares. I only executed sell orders that particular day. At closing last hour, you can buy or sell 100,000 shares "market on close" order without any problem, cuz shares trades between 200,000 to 5 million at the last tick